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Amber/Copal
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
amber / copal yellow, golden brown	2 - 2.5	no treatment	n/a	n/a	n/a	Copal is very soft and less stable than amber when left untreated. Avoid excessive exposure to strong light, heat or any chemicals.
	2 - 2.5	heated to create sun spangles	to improve appearance, deepen color, add spangles	frequently	good to very good	Amber is very soft, so be mindful of scratching. Avoid abrasives, ultrasonic, solvents and heat. Avoid prolonged direct sunlight, avoid alcohol and perfumes. Requires gentle handling.	HE
	2 - 2.5	heated	to improve clarity and darken color	frequently	very good		HE
	2 - 2.5	dyed/stained	to alter color	rarely	variable		DYED
	2 - 2.5	pressed and dyed	to create color, clarify and make gem larger	occasionally	very good to excellent		PRS
amber / copal green	2 - 2.5	blacken bottom of cab	to create green color face up	occasionally	excellent	Amber is very soft, so be mindful of scratching. Avoid abrasives, ultrasonic, solvents and heat. Requires gentle handling.	BLKND
	2 - 2.5	heat and pressure in an autoclave	to create color and mature copals	usually	excellent		HP
		dyed	to create color	frequently	good to very good		DYED
	2 - 2.5	pressed and dyed	to create color, and a larger gem	occasionally	excellent		PRS
amber / copal red	2 - 2.5	heated	to create color	frequently	good to very good	Amber is very soft, so be mindful of scratching. Avoid abrasives, ultrasonic, solvents and heat. Avoid prolonged direct sunlight, avoid alcohol and perfumes. Requires gentle handling.	HE
		dyed	to create color	frequently	good to very good		DYED
	2 - 2.5	pressed and dyed	to create color, and a larger gem	occasionally	excellent		PRS
amber / copal doublet - all colors	2 - 2.5	assembled	to alter color	occasionally	good	Amber is very soft, so be mindful of scratching. Avoid abrasives, ultrasonic, solvents and heat. Requires gentle handling.	AS

Amblygonite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
amblygonite, yellow and colorless	5.5 - 6	no treatment	n/a	n/a	n/a	Gentle wear, can be brittle. Avoid high temperatures.
amblygonite blue, green, yellow	5.5 - 6	irradiated	to alter color	frequently	good		IRR
Montebrasite, (amblygonite)	5.5 - 6	no treatment	n/a	n/a	n/a	Gentle wear, can be brittle

Ammolite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
ammolite doublet	3.5 - 4	assembled	to improve durability	frequently	fair to good	Ammolite is very soft, so be mindful of scratching. Avoid abrasives, ultrasonic, solvents and heat. Requires gentle handling.	AS
ammolite triplet	6	assembled glass top	to improve durability	frequently	excellent	Avoid abrasives, ultrasonic, solvents and heat. Requires gentle handling.	AS
ammolite triplet	7	assembled quartz top	to improve durability	frequently	excellent		AS
ammonite (fossil)	3.5 - 4	no treatment	n/a	n/a	n/a	Normal care

Andalusite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
andalusite	7 - 7.5	no treatment	n/a	n/a	n/a	Normal Care
	7 - 7.5	heated	to improve color	occasionally	excellent		HE
chiastolite	5 - 5.5	no treatment	n/a	n/a	n/a	Normal Care
viridine	7 - 7.5	no treatment	n/a	n/a	n/a	Normal Care

Apatite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
apatite green	5	no treatment	n/a	n/a	n/a	Apatite is moderately soft, so be mindful of scratching. Avoid ultrasonic cleaners.
apatite blue and yellow	5	heated	to improve color	frequently	good		HE
	5	irradiated	to improve color	occasionally	good		IRR
cat's-eye, apatite	5	no treatment	n/a	n/a	n/a	Apatite is moderately soft, so be mindful of scratching. Avoid ultrasonic cleaners.
	5	heated	to improve color	frequently	good		HE

Aragonite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
aragonite all colors	3.5 - 4	no treatment	n/a	n/a	n/a	Aragonite is very soft, so be mindful of scratching. It is easily attacked and dissolved by acids such as vinegar. Avoid abrasives, ultrasonic, solvents and heat. Aragonite is generally unsuitable for jewelry
	3.5 - 4	dyed	to alter color	sometimes	fair to good		DYED
	3.5 - 4	waxed/oiled	to improve finish and durability	sometimes	fair to good		W/O

Azurite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
azurite	3.5 - 4	no treatment	n/a	n/a	n/a	Azurite is very soft, so be mindful of scratching. Avoid abrasives, ultrasonic, solvents and heat. Azurite is generally unsuitable for jewelry
	3.5 - 4	coated	to improve appearance and durability	occasionally	fair to good		CTD
	3.5 - 4	filled with oil/resin and polymer	to stabilize & improve appearance	occasionally	good		INF

Azurmalachite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
azurmalachite	3.5 - 4	no treatment	n/a	n/a	n/a	Azurmalachite is very soft, so be mindful of scratching/breaking. Avoid abrasives, ultrasonic, solvents and heat.
	3.5 - 4	impregnated	to improve appearance and durability	rarely	fair to good		IMP
	3.5 - 4	filled with oil/resin and polymer	to improve appearance and durability	rarely	good		FF

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Bastnasite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
bastnasite	4 - 4.5	not known to be treated	n/a	n/a	n/a	Gentle wear, moderately soft and brittle. Not suitable for jewelry.

Benitoite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
benitoite	6.5	not known to be treated	n/a	n/a	n/a	Normal, gentle care.
	6.5	heated	to improve color	sometimes	fair to good		HE

Beryl
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
aquamarine (beryl)	7.5 - 8	no treatment	n/a	n/a	n/a	Normal Care
	7.5 - 8	heated	to improve color	almost always	excellent		HE
bixbite, red (beryl)	7.5 - 8	oiled/resin infused	to improve clarity and appearance	commonly	fair to good, may require maintenance	Avoid ultrasonic cleaners, and harsh chemicals.	INF
	7.5 - 8	Opticon/ExCel™	to improve clarity and appearance	sometimes	very good	Normal Care	FF
goshenite, colorless (beryl)	7.5 - 8	not known to be treated	n/a	n/a	n/a	Normal Care
green (beryl)	7.5 - 8	not known to be treated	n/a	n/a	n/a	Normal Care
heliodor yellow (beryl)	7.5 - 8	irradiated	to produce color	frequently	variable	Normal Care, but some stones may fade in prolonged exposure to light or heat.	IRR
emerald trapiche emerald (beryl)	7.5 - 8	no treatment	n/a	extremely rare	n/a	Normal Care
	7.5 - 8	dyed/stained	to alter color	occasionally	variable	Avoid extreme heat, temperature changes, steaming, chemicals and ultrasonic cleaners.	DYED
	7.5 - 8	fracture filled with oil/resin	to improve clarity and appearance	almost always	fair to good, may require maintenance	Avoid extreme heat, temperature changes, steaming, chemicals and ultrasonic cleaners. In addition to the above precautions: Avoid jeweler's torch and recutting.	FF
	7.5 - 8, possibly lower	fracture filled w/ hardened resin	to improve clarity and appearance	sometimes	fair to good		FF
	7.5 - 8, possibly lower	ExCel™	to improve clarity and appearance	sometimes	very good	Normal Care	FF
maxixe blue (beryl)	7.5 - 8	irradiated	to create the blue color	always	poor	Maxixe beryl is very special. Avoid prolonged exposure to light and heat to avoid quick fading of color.	IRR
morganite pink, peach (beryl)	7.5 - 8	no treatment	n/a	n/a	n/a	Normal Care
	7.5 - 8	heated	to improve color	commonly	excellent		HE
	7.5 - 8	irradiated	to produce color	commonly	excellent		IRR

Bone / Ivory
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
bone / ivory	2 - 3	no treatment	n/a	n/a	n/a	Requires gentle handling. Bone and ivory are very soft and may discolor with time. Be mindful of scratching.
	2 - 3	bleached	to improve color	commonly	good	Bone and ivory are very soft and may discolor with time. Discoloration is due to porosity/absorption of body oils or other substances from wearing. Be mindful of scratching. Avoid chemicals and ultrasonic cleaners. Requires gentle handling	BL
	2 - 3	dyed/stained	to alter color or to look aged	often	good		DYED
	2 - 3	impregnated	to minimize porosity	occasionally	good		IMP
mammoth (ivory)	2 - 3	impregnated / bleached	to improve appearance	commonly	good	Mammoth ivory is very soft and may discolor with time. Discoloration is due to porosity/absorption of body oils or other substances from wearing. Be mindful of scratching Avoid chemicals and ultrasonic cleaners. Requires gentle handling	IMP
horn	2.5	no treatment	n/a	n/a	n/a	Horn is a soft, organic product. Avoid heat, chemicals and ultrasonic cleaners. Requires gentle handling.
	2.5	heated	to shape	often	fair		HE
shark teeth	***	not known to be treated	n/a	n/a	n/a	Most shark teeth are actually fossils. Gentle Care.
walrus tusk	2.5	no treatment	n/a	n/a	n/a	Walrus tusks are very soft and may discolor with time. Discoloration is due to porosity/absorption of body oils or other substances from wearing. Be mindful of scratching. Avoid chemicals and ultrasonic cleaners. Requires gentle handling
	2.5	bleached	to even color, improve lustre	often	good		BL
	2.5	stained	to add color, appear aged	often	good		STN
whale teeth	2.5	no treatment	n/a	n/a	n/a	Whale teeth are very soft and may discolor with time. Discoloration is due to porosity/absorption of body oils or other substances from wearing. Be mindful of scratching. Avoid chemicals and ultrasonic cleaners. Requires gentle handling
	2.5	bleached	to even color, improve lustre	often	very good		BL
	2.5	stained	to add color, appear aged	sometimes	fair to good		STN

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Calcite - Marble
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
aragonite all colors	3.5 - 4	no treatment	n/a	n/a	n/a	Aragonite is very soft, so be mindful of scratching. It is easily attacked and dissolved by acids such as vinegar. Avoid abrasives, ultrasonic, solvents and heat. Aragonite is generally unsuitable for jewelry.
	3.5 - 4	dyed	to alter color	occasionally	fair to good		DYED
	3.5 - 4	waxed/oiled	to improve finish and durability	occasionally	fair to good		W/O
cats eye calcite	3	not known to be treated	n/a	n/a	n/a	Gentle care, moderately soft. Avoid ultrasonic cleaners, vinegar, harsh cleaners.
marble	3	no treatment	n/a	n/a	n/a	Gentle care, moderately soft. Avoid ultrasonic cleaners, vinegar, harsh cleaners.
	3	dyed	to add color	frequently	good to excellent	Gentle care, moderately soft. Avoid ultrasonic cleaners, vinegar, harsh cleaners.	DYED
	3	lacquered	to improve appearance and durability	occasionally	fair to good	Gentle care, moderately soft. Avoid ultrasonic cleaners, vinegar, harsh cleaners.	STB

Cavansite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
cavansite	3 - 4	no treatment	n/a	n/a	n/a	Gentle handling (specimen)

Cerussite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
cerussite	3.5	not known to be treated	n/a	n/a	n/a	Very soft gentle care, not suitable for jewelry.

Chalcedony (polycrystalline anf microcrystaline quartz)
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
agate(quartz)	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	bleached/dyed/stained	to alter color	commonly	good to excellent	Avoid sudden temperature changes, chemicals, and ultrasonic cleaners. In addition to above precautions: avoid perfumes, and hairsprays.	BL
blue chalcedony (quartz)	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	dyed/stained	to alter color	commonly	fair to good	Avoid harsh chemicals, accetone and ultrasonic cleaners. Can be affected by perspiration.	DYED
blue, green, paraiba color chalcedony (quartz)	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	irradiated	to alter color	commonly	fair to good	Avoid abrasives, ultrasonic, solvents and heat. Some stones may fade in light or heat.	IRR
	6.5	dyed/stained	to alter color	almost always	poor to fair	Avoid harsh chemicals, acetone and ultrasonic cleaners. Some stones may fade in light or heat. Can be affected by perspiration.	DYED
banded agate (chalcedony)	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	dyed/stained	to alter color	commonly	excellent		DYED
black onyx (chalcedony)	6.5	dyed/stained	to alter color	almost always	fair to good	Avoid harsh chemicals, acetone and ultrasonic cleaners. Dye could run.	DYED
	6.5	irradiated	to darken color	commonly	excellent	normal care	IRR
bloodstone (chalcedony)	6 - 6.5	not known to be treated	n/a	n/a	n/a	Normal Care
carnelian / sard (chalcedony)	6.5	heated	to improve color	usually	excellent	Normal Care	HE
	6.5	dyed/stained	to alter color	often	good to excellent	Avoid harsh chemicals, acetone and ultrasonic cleaners.	DYED
cat's eye, chalcedony	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	heated	to alter color	usually	excellent		HE
chrysocolla(chalcedony)	2 - 6 depending on purity	not known to be treated	n/a	n/a	n/a	Chrysocolla is very soft, so be mindful of scratching. Requires gentle handling.
chrysoprase (chalcedony)	6.5	not known to be treated	n/a	n/a	n/a	Normal Care
	6.5	heated	to improve color	occasionally	excellent		HE
dendritic agate (chalcedony)	6.5	not known to be treated	n/a	n/a	n/a	Normal Care
dumortierite quartz	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	oiling	to reduce appearance of natural fissures	occasionally	fair	Normal Care	O
fire agate (chalcedony)	6.5	not known to be treated	n/a	n/a	n/a	Normal Care
jasper (quartz)	6 - 6.5	no treatment	n/a	n/a	n/a	Avoid chemicals, steam, and ultrasonic cleaners.
	6 - 6.5	dyed	to add color	occasionally	fair to excellent		DYED
jasper beads (quartz)	6 - 6.5	lacquered	prevent porosity	occasionally	fair	Avoid chemicals, steam, and ultrasonic cleaners.
moss agate (quartz)	6.5	not known to be treated	n/a	n/a	n/a	Normal Care
petrified wood (quartz)	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	bleached	to remove color	occasionally	excellent		BL
	6.5	heated	to improve color	occasionally	very good		HE
pietersite, henanite	6.5	not known to be treated	n/a	n/a	n/a	Normal Care
hawk's-eye, blue tiger's eye	6.5-7	no treatment	n/a	n/a	n/a	Normal Care
	6.5-7	chemical bleaching with acid or bleaching agents	to alter color	occasionally	excellent		BL
tiger's-eye, brown	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	chemical bleaching with acid or bleaching agents	to lighten color	occasionally	excellent		BL
tiger's-eye, red	6.5	heated	to change from gold to red	always	excellent	Normal Care	HE
	6.5	chemical bleaching with acid or bleaching agents	to alter color	occasionally	excellent		BL
	6.5	dyed	to alter color	occasionally	very good	Avoid sudden temperature changes, chemicals, steam and ultrasonic cleaners.	DYED

Charoite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
charoite	5-6	no treatment	n/a	n/a	n/a	Normal Care
	5-6	impregnated	to improve durability	commonly	good	Avoid hot water, household chemicals, and ultrasonic cleaners	IMP

Chrysoberyl
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
alexandrite (chrysoberyl)	8.5	not known to be treated	n/a	n/a	n/a	Normal Care
	8.5	oiled	to improve clarity	occasionally	good	avoid ultrasonics, heat, and harsh cleaners	O
cat's-eye (chrysoberyl)	8.5	no treatment	n/a	n/a	n/a	Normal Care
	8.5	heated	to improve color	occasionally	excellent	Normal Care	HE
brown, yellow, green (chrysoberyl)	8.5	no treatment	n/a	n/a	n/a	Normal Care
	8.5	irradiated	to create color	occasionally	excellent	Normal Care	IRR
	8.5	heated	to improve color	occasionally	excellent	Normal Care	HE

Clinohumite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
clinohumite	6	not known to be treated	n/a	n/a	n/a	Requires gentle handling.

Coral
Please be assured that JTV goes to great lengths to comply with all laws protecting endangered species.
The term "polycoral" is used to describe products that are composed of coral fragments (and often other ocean products) which are then dyed and bonded with polymers.
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
bamboo / sponge (coral, polycoral)	3-4	no treatment	n/a	n/a	n/a	Avoid ultrasonic cleaners, steam and extreme heat.
	3 - 4	impregnated waxed/oiled	to improve appearance and luster	frequently	good		IMP
	3 - 4	dyed/stained	to alter color	frequently	good		DYED
	3 - 4	assembled product	to create coral effect from smaller stones	frequently	fair to good		AS
precious coral, branch coral	3 - 4	dyed/waxed	to improve color and texture	frequently	good	Avoid ultrasonic cleaners, steam and extreme heat.	DYED
	3 - 4	impregnated with colorless wax or oil	to improve the quality of material for shaping and polishing	frequently	good		IMP
	3 - 4	impregnated with plastic	to improve quality of material for shaping and reploshing	frequently	very good		IMP
	3 - 4	assembled product	to create coral effect from smaller stones	frequently	fair to good		AS
black coral	3 - 4	no treatment	n/a	n/a	n/a	Avoid ultrasonic cleaners, steam and extreme heat.
	3 - 4	waxed	to improve overall appearance and luster	frequently	fair to good
golden coral	3 - 4	bleached	to bring out color	always	excellent	Avoid ultrasonic cleaners, steam and extreme heat.
	3 - 4	waxed	to improve overall appearance and luster	frequently	fair to good

Corundum
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
ruby (corundum)	9	no treatment(extremely rare)	n/a	n/a	n/a	Normal Care
	9	heated	to improve colorand clarity	usually	excellent		HE
	9	filled/flux healed	to improve clarity	commonly	good to excellent		FH
	9	Beryllium lattice diffusion	to improve color	occasionally	excellent	Avoid recutting, otherwise Normal Care	BE DIF
	6 - 9	lead glass filled (fissure filled) See Hybrid	to improve clarity and color	commonly	poor	Avoid common household chemicals, steam cleaners, and ultrasonic cleaners .Avoid jewelers torches.	LGF
	9	surface diffusion	to create asterism or color	occasionally	good	Avoid repolishing / recutting and scratching.	DIF
	9	dyed/stained with colored oils or polymers	to improve color and clarity	occasionally	poor	Avoid harsh chemicals, heat and ultrasonic cleaners.	DYED
ruby beads	9	waxed/oiled	to improve clarity and luster	frequently	poor	Avoid harsh chemicals, heat and ultrasonic cleaners.	W
star ruby all (corundum)	9	no treatment	n/a	n/a	n/a	Avoid jewelers torches, otherwise Normal Care
	6 - 9	lead glass filled (fissure filled) SeeHybrid	to improve clarity, fill cracks	occasionally	poor to fair	Avoid common household chemicals, steam cleaners, and ultrasonic cleaners. Avoid jeweler's torches.	LGF
	9	surface diffusion	to implant star	occasionally	excellent	Avoid repolishing / recutting, scratching and jeweler's torches.	DIF
	9	heated	to improve color	sometimes	excellent	Avoid jewelers torches, otherwise Normal Care	HE
sapphire, blue (corundum)	9	no treatment(rare)	n/a	n/a	n/a	Normal Care
	9	heated	to improve colorand clarity	usually	excellent	Normal Care	HE
	9	beryllium lattice diffusion	to lighten color	occasionally	excellent	Avoid recutting, otherwise Normal Care	BE DIF
	9	surface diffusion	to create or improve color	occasionally	good	Avoid chipping or repolishing	DIF
	6 - 9	lead glass filled (fissure filled) See Hybrid	to add color and improve clarity	rarely	fair to poor	Avoid common household chemicals, steam cleaners, ultrasonic cleaners and a jewelers torch.	LGF
sapphire, fancy (green, orange, purple, pink, padparadscha, yellow) (corundum)	9	no treatment	n/a	n/a	n/a	Normal Care
	9	heated	to improve color and clarity	usually	excellent	Normal Care	HE
	6 - 9	lead glass filled (fissure filled) See Hybrid	to improve clarity	occasionally	poor	Avoid common household chemicals, steam cleaners, ultrasonic cleaners, and jewelers torches.	LGF
	9	beryllium lattice diffusion	to improve color	commonly	excellent	Avoid recutting, otherwise Normal Care	BE DIF
sapphire, star blue (corundum)	9	no treatment	n/a	n/a	n/a	Avoid jewelers torches, otherwise Normal Care
	9	heated	improve color	sometimes	excellent		HE
	9	surface diffusion	to implant star	often	excellent	Avoid repolishing / recutting, scratching and jeweler's torches.	DIF
sapphire, stargray - white (corundum)	9	no treatment	n/a	n/a	n/a	Avoid jewelers torches, otherwise Normal Care
	9	surface diffusion	to implant star	occasionally	Excellent	Avoid repolishing / recutting, scratching and jeweler's torches.	DIF
sapphire, black star (corundum)	9	no treatment	n/a	n/a	n/a	Normal Care
	9	lacquered	prevent flaking	often	fair	Avoid harsh solvents and ultrasonic cleaners
	6 - 9	lead glass filled (fissure filled) See Hybrid	reduce appearance of cracks	sometimes	fair to poor	Avoid common household chemicals, steam cleaners, and ultrasonic cleaners.	LGF

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Danburite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
danburite	7-7.5	not known to be treated	n/a	n/a	n/a	Normal Care

Diamond
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
diamond normal color range D - Z	10	no treatment	n/a	n/a	n/a	Normal Care
	10	HPHT (high pressure,high temperature)	to lighten or change color	occasionally	excellent	Normal Care	HPHT
	10	lasered & bleached with acid	to improve clarity	often	very good	Normal Care
	10	fracture filled	to improve clarity	occasionally	fair to very good	Avoid extreme heat, temperature changes, steaming, chemicals and ultrasonic cleaners.In addition to the above precautions: Avoid jeweler's torch and recutting.	FF
	10	CVD coated	to add or minimize color	rarely	poor to good	Color may be affected by polishing, recutting, ultrasonic cleaners, alcohol, and harsh chemicals.	CVD
diamond champagne	10	no treatment	n/a	n/a	n/a	Normal Care
	10	HPHT (high pressure,high temperature)	to improve color	occasionally	excellent		HPHT
diamond fancy color	10	no treatment	n/a	n/a	n/a	Normal Care
	10	HPHT (high pressure,high temperature)	to improve color	occasional/increasingly common	excellent	Normal Care	HPHT
	10	lasered & filled	to improve clarity	occasionally	very good
	10	irradiated	to create color	often	very good to excellent		IRR
	10	fracture filled	to improve clarity	sometimes	fair to very good	Avoid extreme heat, temperature changes, steaming, chemicals and ultrasonic cleaners.In addition to the above precautions: Avoid jeweler's torch and recutting.	FF
	10	CVD coated	to add color	sometimes	poor to good	Color may be affected by polishing, recutting, ultrasonic cleaners, alcohol, and harsh chemicals.	CVD

Diaspore
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
diaspore zultanite™	6.5 - 7	not known to be treated	n/a	n/a	n/a	Cleaves easily, or is known to brittleness. Avoid ultrasonic cleaners. Wear with care.
cat's eye diaspore zultanite™	6.5 - 7	oiled	to improve appearance	commonly	fair	Cleaves easily, or is prone to brittleness. Avoid ultrasonic cleaners, heat and chemicals. Wear with care.	O

Diopside
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
chrome diopside	5.5	not known to be treated	n/a	n/a	n/a	Diopside is moderately soft, so be mindful of scratching. Avoid abrasives and solvents.
black star (diopside)	5.5	not known to be treated	n/a	n/a	n/a
Shanseres (diopside)	5.5	not known to be treated	n/a	n/a	n/a

Dolomite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
dolomite	3.5 - 4	waxed/lacquered	to improve finish and durability	frequently	fair	Normal, gentle care.	W
dolomite (laguna lace agate)	3.5 - 4	dyed	to add colors	frequently	good	gentle care, avoid heat and harsh chemicals	DYED

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Enstatite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
enstatite	5.5	not known to be treated	n/a	n/a	n/a	Moderately soft, so be mindful of scratching. Requires gentle handling.
hypersthene	5-6	not known to be treated	n/a	n/a	n/a

Euclase
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
euclase	7.5	not known to be treated	n/a	n/a	n/a	Cleaves easily, or is prone to brittleness. Avoid ultrasonic cleaners.Wear with care.

Eudialyte
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
eudialyte	5 - 6	not known to be treated	n/a	n/a	n/a	Moderately soft and brittle, so be mindful of sratching.

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Feldspar (orthoclase)
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
amazonite (microcline feldspar)	6.5	no treatment	n/a	n/a	n/a	Avoid hard wear, heat, chemicals and ultrasonic cleaners.
	6.5	heated	to improve color	occasionally	very good		HE
	6.5	dyed	to improve color	occasionally	very good		DYED
	6.5	impregnated with colorless wax or oil	to improve overall appearance and luster	occasionally	good to fair		IMP
	6.5	impregnated with hardening agents or plastic	to improve appearance and durability	usually	very good		IMP
moonstone, adularia (orthoclase feldspar)	6 - 6.5	not known to be treated	n/a	n/a	n/a	Normal Care
yellow orthoclase	6 - 6.5	not known to be treated	n/a	n/a	n/a	Normal Care
sunstone (orthoclase feldspar)	6 - 6.5	not known to be treated	n/a	n/a	n/a	Normal, gentle handling. Avoid ultrasonic cleaners.

Feldspar (plagioclase)
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
albite (plagioclase feldspar)	6 - 6.5	not known to be treated	n/a	n/a	n/a	Normal Care
andesine-labradorite Red / Green / Orange (plagioclase feldspar)	6 - 6.5	no treatment	n/a	n/a	n/a	Normal Care
	6 - 6.5	diffused	to alter color	commonly	excellent	Normal Care	DIF
labradorite (plagioclase feldspar)	6 - 6.5	not known to be treated	n/a	n/a	n/a	Normal, gentle handling
	6 - 6.5	oiled	to improve appearance	occasionally	fair to good	Avoid ultrasonic cleaners	O
labradorite yellow (plagioclase feldspar)	6 - 6.5	no treatment	n/a	n/a	n/a	Normal, gentle handling
	6 - 6.5	irradiated	to improve color	commonly	good	Normal, gentle handling. Avoid heat.	IRR
	6 - 6.5	CVD coated	to add color	occasionally	fair to good	Color may be affected by polishing, recutting, ultrasonic cleaners, alcohol, and harsh chemicals.	CVD
Larvikite - Gabbro (plagioclase feldspar)	6 - 6.5	not known to be treated	n/a	n/a	n/a	Normal, gentle handling.
	6 - 6.5	waxed	to improve appearance	occasionally	fair to good	Avoid ultrasonic cleaners	W
sunstone (plagioclase feldspar)	6 - 6.5	not known to be treated	n/a	n/a	n/a	Normal, gentle handling. Avoid ultrasonic cleaners.

Fluorite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
fluorite	4	no treatment	n/a	n/a	n/a	Very soft stone, requires gentle handling. Color can be reversed with heat - avoid heat and jeweler torches.
	4	heated	to improve color	occasionally	fair to good		HE
	4	irradiated	to alter/improve color	frequently	fair to good		IRR

Fossils
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
trilobites		not known to be treated	n/a	n/a	n/a	Normal care

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Garnet
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
almandite	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
anthill garnet (chrome pyrope)	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
color change	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
demantoid (andradite)	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	low temperature heat	to improve color	often	excellent		HE
hessonite / imperial (grossular)	7	not known to be treated	n/a	n/a	n/a	Normal Care
hyderabad	7	not known to be treated	n/a	n/a	n/a	Normal Care
Mali	6.5 - 7	not known to be treated	n/a	n/a	n/a	Normal Care
Masasi™ Bordeaux Garnet (almandine, spessartite, grossular)	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
Mozambique	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
pyrope	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
rhodolite	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
spessartite	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
Sunset Native™ Garnet (almandine, pyrope, grossular, and spessartine)	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
Tanga™ (almandite/pyrope)	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
tsavorite (grossular)	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
umbalite, malaya, malaia	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
uvarovite	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care

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Hayüne
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
haüyne / haüynit	5.5 - 6	not known to be treated	n/a	n/a	n/a	Normal, gentle handling

Hematite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
hematite	5.5 - 6.5	not known to be treated	n/a	n/a	n/a	Normal Care
hematine	6.5	man-made	n/a	n/a	n/a	Normal Care

Hemimorphite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
hemimorphite	4.5 - 5	not known to be treated	n/a	n/a	n/a	Gentle care, moderately soft. Avoid ultrasonic cleaners.

Hybrid
New category of stones: A stone with natural and artificial components, where the two cannot be separated. New category created by a new generation of treatments that add materials to a natural base material. In most cases, undesirable elements of a natural material are removed and replaced by added artificial gem material; glass, polymers or synthetic material. Most require special care. Listing of stones will be added in the coming months.
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
ruby (corundum) lead glass filling Mahaleo Ruby	5 - 6 (will vary depending on the amount of glass filling used)	filled	color and clarity enhancement	always	will vary depending on the amount of glass filling used	Special care required. Avoid ordinary household cleaners, acidic cleaners, acidic foods (lemon juice, vinegar, etc), steam and ultra sonic cleaners. Clean with a damp cloth.	LGF
sapphire (corundum) lead glass filling	5 - 6 (will vary depending on the amount of glass filling used)	filled	color and clarity enhancement	always	will vary depending on the amount of glass filling used	Special care required. Avoid ordinary household cleaners, acidic cleaners, acidic foods (lemon juice, vinegar, etc), steam and ultra sonic cleaners. Clean with a damp cloth.	LGF
sapphire, pink (corundum) lead glass filling Mahaleo Sapphire	5 - 9 (will vary depending on the amount of glass filling used)	filled	color and clarity enhancement	always	will vary depending on the amount of glass filling used	Special care required. Avoid ordinary household cleaners, acidic cleaners, acidic foods (lemon juice, vinegar, etc), steam and ultra sonic cleaners. Clean with a damp cloth.	LGF
B-Jade	5 - 7	acid treated and filled	to improve color and clarity	always	good stability	Gentle care required: Avoid heat, harsh chemicals, and ultrasonic cleaners	B-Jade

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Imitation / Simulant / Man-Made
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
casilica	5 - 6	man-made	n/a	n/a	n/a	Gentle Care
cat's eye glass, fiber optic glass	5 - 6	man-made	n/a	n/a	n/a	Normal Care
goldstone (glass)	5 - 6	man-made	n/a	n/a	n/a	Normal Care
helenite (glass)	5 - 5.5	man-made	n/a	n/a	n/a	Normal Care
hematine	6.5	man-made	n/a	n/a	n/a	Normal Care
glass, man-made	5 - 6	man-made	n/a	n/a	n/a	Normal Care
mandarin ice	5 - 6	man-made	n/a	n/a	n/a	Normal Care
opal (artificial polymer based)	4 - 5	man-made	n/a	n/a	n/a	Normal Care
paraiba ice (glass)	5 - 6	man-made	n/a	n/a	n/a	Normal Care
Pearlfection™	3 - 4	simulant	n/a	n/a	n/a	Avoid cosmetics, perfumes, hairsprays, heat and household chemicals	DYED
roman glass	5 - 6	man-made	n/a	n/a	n/a	Avoid household chemicals
zandrite (glass)	5 - 6	man-made	n/a	n/a	n/a	Normal Care

Iolite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
iolite (cordierite)	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care

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Jadeite & Nephrite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
jadeite jade all colors	6.5 - 7	no treatment	n/a	n/a	n/a	Normal Care. Avoid heat, harsh chemicals, and ultrasonic cleaners.
	6.5 - 7	waxed/oiled	to improve appearance	commonly	good		W
	6.5 - 7	Bleached/impregnated/dyed (B-Jade)	to improve appearance	frequently	good	Gentle care required: Avoid heat, harsh chemicals, and ultrasonic cleaners.	B-Jade
	6.5 - 7	dyed/stained	to add color	often	good	Avoid strong light, chemicals, and ultrasonic cleaners.	DYED
nephrite jade all colors	6 - 6.5	no treatment	n/a	n/a	n/a	Normal Care
	6 - 6.5	dyed/stained	to add color	rarely	unknown	Avoid strong light, harsh chemicals, and ultrasonic cleaners. Discoloration may occur with time.	DYED

Jeremejevite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
jeremejevite	6.5 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care

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Kornerupine
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
kornerupine	6.5	not known to be treated	n/a	n/a	n/a	Normal, gentle handling. Avoid ultrasonic cleaners.
kornerupine cat's eye	6.5	not known to be treated	n/a	n/a	n/a

Kyanite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
kyanite	5 & 7, depending on direction	no treatment	n/a	n/a	n/a	Moderately soft and brittle, so be mindful of scratching.
	5 & 7, depending on direction	heated	to alter color	rarely	research in progress		HE
	5 & 7, depending on direction	oiled/resin infused	to improve clarity	occasionally	fair	Moderately soft and brittle, so be mindful of scratching.	INF

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Lab-Created
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
alexandrite	8.5	lab created	n/a	n/a	n/a	Normal Care
cubic zirconia	8 - 8.5	lab created	n/a	n/a	n/a	Normal Care
	8 - 8.5	CVD coated	to add optic effects	rarely	poor to good	Color may be affected by polishing, recutting, ultrasonic cleaners, alcohol, and harsh chemicals. Coating can be scratched.	CVD
forsterite	7	lab created	n/a	n/a	n/a	Normal Care
opal	6	lab created	n/a	n/a	n/a	Normal, gentle care
rutile	6 - 6.5	lab created	n/a	n/a	n/a	Normal, gentle care
sandstone	5 - 6	lab created	n/a	n/a	n/a	Normal, gentle care
stronium titanate	5 - 5.5	lab created	n/a	n/a	n/a	Normal, gentle handling Stronium Titanate is a soft stone, so be mindful of scratching.
yttrium aluminum garnet (YAG)	8.5	lab created	n/a	n/a	n/a	Normal Care

Lapis Lazuli
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
lapis lazuli	5 - 6	no treatment	n/a	n/a	n/a	Normal, gentle handling. Avoid exposure to acids, heat and ultrasonic cleaners.
	5 - 6	waxed/oiled	to improve appearance	commonly	fair		W
	5 - 6	heated/dyed/stained	to improve color	commonly	poor to good		HE
	5 - 6	lacquered	to improve durability and appearance	rarely	good		CTD

Lazulite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
lazulite	5 - 6	not known to be treated	n/a	n/a	n/a	Avoid strong light, chemicals, and ultrasonic cleaners.

Lepidolite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
lepidolite	2.5 - 3	not known to be treated	n/a	n/a	n/a	Lepidolite is very soft, so be mindful of scratching. Requires gentle handling

Larimar
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
larimar (pectolite)	4.5 - 5	not known to be treated	n/a	n/a	n/a	Larimar is soft, so be mindful of scratching. Requires gentle handling
	4.5 - 5	stabilized/impregnated	to improve stability and durability	occasionally	very good	Gentle care, avoid heat and harsh chemicals.	STB

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Magnesite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
magnesite	4	dyed & stabilized	to imitate other materials	frequently	very good	Gentle care, avoid heat and harsh chemicals.	DYED

Malachite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
malachite	3.5 - 4	no treatment	n/a	n/a	n/a	Malachite is very soft, so be mindful of scratching. Avoid chemicals, abrasives, heat and ultrasonic cleaners.
	3.5 - 4	coated with colorless wax	to improve appearance	occasionally	fair		W
	3.5 - 4	impregnated with plastic or other hardening agents	to improve appearance and durability	often	good		IMP
	3.5 - 4	dyed	to improve color uniformity	occasionally	good		DYED

Maw Sit Sit
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
maw sit-sit	6 - 7	not known to be treated	n/a	n/a	n/a	Normal Care

Muscovite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
muscovite	2.5	not known to be treated	n/a	n/a	n/a	Muscovite is very soft, so be mindful of scratching. Requires gentle handling

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Natural Glass
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
moldavite (natural glass)	5.5	not known to be treated	n/a	n/a	n/a	Normal, gentle care
obsidian (volcanic glass)	5 - 5.5	not known to be treated	n/a	n/a	n/a	Avoid heat, chemicals, and ultrasonic cleaners.
glass, Lybian desert	5 - 5.5	not known to be treated	n/a	n/a	n/a	Normal, gentle care

Natural Rock
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
goldenite jade	6 - 6.5	layered gold leaf	adds gold veins	always	good	Avoid abrasives, chemicals, and ultrasonic cleaners.
rhyolite (igneous rock)	6 - 7	not known to be treated	n/a	n/a	n/a	Normal Care

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Opal
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
fire opal	5.5 - 6	no treatment	n/a	n/a	n/a	Avoid water, heat and solvents. Fire Opal is moderately soft, so be mindful of scratching.
	5.5 - 6	impregnated	to improve stability and durability	commonly	good		IMP
	5.5 - 6	dyed/stained	to add color	sometimes	good		DYED
ethiopian opal	5 - 6	no treatment	n/a	n/a	n/a	Avoid steamers or ultrasonics; keep away from harsh cleaning agents or perfume; simply clean with a soft cloth. Keep away from any fluids or oils, as they can be absorbed and alter appearance and or crack the stone. Avoid all types of heat.
	5 - 6	dyed	to add color	occasionally	very good to excellent		DYED
	5 - 6	smoked	to darken body color	occasionally	very good to excellent		SM
	5 - 6	stabilized/impregnated	to improve stability and durability	occasionally	very good		STB
boulder opal	6	no treatment	n/a	n/a	n/a	Normal Care
	6	oiled/resin infused	to improve appearance and clarity	occasionally	fair	Avoid heat, chemicals, ultrasonic, and repolishing.	INF
cat's-eye opal	6	impregnated	to improve appearance and durability	usually	good	Avoid heat, chemicals, and ultrasonic cleaners.	IMP
common opal (non play-of-color opal)	6 - 6.5	no treatment	n/a	n/a	n/a	Normal gentle care
common opal (non play-of-color opal)	6 - 6.5	dyed	to add color	occasionally	fair to good	Avoid steaming, chemicals, and ultrasonic cleaners	DYED
matrix opal	6 or possibly lower	no treatment	n/a	n/a	n/a	Normal Care, gentle care
	5-6	stabilized/impregnated	to improve stability and durability	occasionally	very good	gentle care, avoid heat and harsh chemicals	STB
	6 or possibly lower	sugar acid/smoke	to darken color	commonly	good	Avoid heat, solvents, recutting and repolishing.
mosaic opal triplet, glass top	5 - 6	assembled product	to create opal effect from smaller stones	commonly	fair to good	Avoid heat, solvents, chemicals, ultrasonic, and repolishing.	AS
mosaic opal triplet, quartz top	7	assembled product	to create opal effect from smaller stones	commonly	fair to good	Avoid heat, solvents, chemicals, ultrasonic, and repolishing.	AS
peruvian opal	6	not known to be treated	n/a	n/a	n/a	Avoid heat, chemicals, and ultrasonic cleaners.
	6	dyed	to enhance color	occasionally	fair good	Avoid temperature changes, steaming, chemicals, and ultrasonic cleaners.	DYED
opal doublet	6	assembled product	to improve color and/or durability	always	n/a	Avoid heat, chemicals, ultrasonic, and repolishing.	AS
opal triplet, glass top	5 - 6	assembled product	to improve color and/or durability	always	fair to good	Avoid heat, solvents, chemicals, ultrasonic, and repolishing.	AS
opal triplet, quartz top	7	assembled product	to improve color and/or durability	always	fair to good	Avoid heat, solvents, chemicals, ultrasonic, and repolishing.	AS
prase opal	6 - 6.5	no treatment	n/a	n/a	n/a	Normal, gentle care
solid play-of-color opal, black, gray, white base	6	no treatment	n/a	n/a	n/a	Avoid excessive heat, solvents, and ultrasonic cleaners.
	6	impregnated, oiled/resin infused	to help prevent crazing	rarely	fair		IMP
	6	coated on bottom	to improve color	occasionally	fair to good		CTD

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Pearl
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
abalone pearl (natural pearl)	2.5 - 4	no treatment	n/a	n/a	n/a	Abalone is very soft, so be mindful of scratching. Avoid sudden temperature changes, chemicals, and ultrasonic cleaners. In addition to above precautions: avoid perfumes, and hairsprays. Requires gentle handling.
conch pearl (natural pearl)	3 - 4	no treatment	n/a	n/a	n/a	Avoid cosmetics, perfumes, hairsprays, heat and household chemicals.
	3 - 4	polishing/filling	to repair	n/a	good
cultured pearl freshwater & saltwater (akoya, freshwater mussel, souffle)	3 - 4	no treatment	n/a	n/a	n/a	Avoid cosmetics, perfumes, hairsprays, heat and household chemicals.
	3 - 4	bleached	to whiten and remove discoloration	usually	excellent		BL
	3 - 4	dyed/stained	to add color	commonly	good		DYED
	3 - 4	dyed/stained, potential colored nuclei	to add color	occasionally	variable		DYED
	3 - 4	irradiated	to create color	occasionally	very good		IRR
	3 - 4	coated	to even color, improve lustre	often - increasingly common	fair to good		CTD
cultured Tahitian, South Sea and keshi	3 - 4	no treatment	n/a	n/a	n/a	Avoid cosmetics, perfumes, hairsprays, heat and household chemicals.
	3 - 4	bleached	to create more even color or lighten	often	very good		BL
	3 - 4	dyed	to add color	commonly	good		DYED
mabe	3 - 4	ASSEMBLED PRODUCT: coated, dyed, bleached, filled w/hardened substance + a mother-of-pearl back.	to improve color and durability	always	fair to very good	Avoid cosmetics, perfumes, hairsprays, heat and household chemicals.	AS
mabe pearl (natural pearl)	3 - 4	no treatment	n/a	n/a	n/a	Avoid cosmetics, perfumes, hairsprays, heat and household chemicals.
	3 - 4	polishing/filling	to repair	n/a	good
natural pearl very rare (scallop, conch, clam, oyster)	3 - 4	bleached	to whiten and remove discoloration	usually	very good	Avoid cosmetics, perfumes, hairsprays, heat and household chemicals.	BL
	3 - 4	dyed/stained w/-w/o heat	to alter color	rarely	good to very good		DYED
Pearlfection™	3 - 4	simulant	n/a	n/a	n/a	Avoid cosmetics, perfumes, hairsprays, heat and household chemicals.	DYED
souffle' pearls	3 - 4	no treatment	n/a	n/a	n/a	Avoid cosmetics, perfumes, hairsprays, heat and household chemicals.

Peridot
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
peridot	6.5	no treatment	n/a	n/a	n/a	Avoid ultrasonic cleaners
	6.5	impregnated, oiled/waxed	to improve appearance	rarely	fair to good	Avoid sudden temperature changes, harsh chemicals, and ultrasonic cleaners.	IMP

Petalite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
petalite	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	irradiated	to improve or alter color	occasionally	good		IRR

Pezzotaite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
pezzotaite	8	not known to be treated	n/a	n/a	n/a	Normal Care

Phenakite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
phenakite	7.5 - 8	not known to be treated	n/a	n/a	n/a	Normal Care, but avoid sudden temperature changes.

Prehnite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
prehnite	6 - 6.5	not known to be treated	n/a	n/a	n/a	Normal Care, but avoid sudden temperature changes.

Psilomelane
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
psilomelane	6.5	no treatment	n/a	n/a	n/a	Normal Care

Phosphosiderite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
phosphosiderite	3.5 - 4	stabilized	to improve stability and durability	almost always	very good	Gentle care, moderately soft. Avoid ultrasonic cleaners, heat and harsh cleaners.	STB

Pyrite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
marcasite (pyrite)	6 - 6.5	not known to be treated	n/a	n/a	n/a	Normal, gentle handling. Avoid acids and chemicals.
pyrite	6 - 6.5	not known to be treated	n/a	n/a	n/a
	3 - 4	gold plated	to look like gold	sometimes	very good
rainbow(pyrite)	6 - 6.5	not known to be treated	n/a	n/a	n/a

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Quartz
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
amethyst	7	no treatment	n/a	n/a	n/a	Avoid extreme heat, avoid jewelers torch
	7	heated/irradiated	to improve color	occasionally	excellent		HE/IRR
ametrine	7	no treatment	n/a	n/a	n/a	Avoid extreme heat, avoid jewelers torch
	7	heated	to improve color	frequently	excellent		HE
blueberry	7	irradiated /annealed	to create color	always	excellent	Normal care	IRR
blue moon quartz	7	heated	to create effect	always	excellent	Normal Care	HE
cavansite	3 - 4	no treatment	n/a	n/a	n/a	Gentle handling (specimen)
citrine (all types)	7	no treatment	n/a	n/a	n/a	Avoid jewelers torches.
	7	heated	to alter color	usually	excellent		HE
lemon citrine ouro verde	7	irradiated	to create color	always	excellent	Normal Care	IRR
dendritic quartz	7	no treatment	n/a	n/a	n/a	Normal Care
	7	heated	to alter color	rarely	excellent	Normal Care	HE
	7	irradiated	to create color	commonly	good	Avoid temperature changes, steaming, chemicals, and ultrasonic cleaners.	IRR
drusy quartz	7	no treatment	n/a	n/a	n/a	Normal care
	7	coated	to create color or iridescence	often	good	Gentle care. Avoid abrasions that can remove or scratch coating.	CTD
	7	CVD	to produce color	frequently	very good	Chipping may reveal natural color, so avoid abrasions. Cannot be re-cut or re-polished. Avoid heat, chemicals, and ultrasonic cleaners.	CVD
	7	heated	to improve color	occasionally	excellent	Normal care	HE
latte quartz	7	irradiated/heated	to alter color	usually	excellent	Normal Care	HE/IRR
lazulated quartz	7	not known to be treated	n/a	n/a	n/a	Avoid heat, temperature changes, steaming, chemicals, ultrasonic cleaners, and repolishing
lilac quartz	7	heated	to improve color	occasionally	excellent	Normal Care	HE
mystic quartz	7	CVD	to produce mystic quartz	always	very good	Chipping may reveal natural color, so avoid abrasions.Cannot be recut or repolished. Avoid heat,chemicals, and ultrasonic cleaners	CVD
pietersite, henanite	6.5	not known to be treated	n/a	n/a	n/a	Normal Care
prasiolite (green quartz)	7	irradiated/ annealed	to alter color	always	very good	Avoid a jeweler's torch.
quartz w/special inclusions (actinolite, confetti, medusa, leopard, strawberry, iodolite)	7	not known to be treated	n/a	n/a	n/a	While they are a 7 in hardness, a proliferation of inclusions may alter this, either strengthening or weakening a material.
quench crackled, emerald green	7	heated/cooled, dyed	to add color and inclusions	commonly	very good	Avoid heat, temperature changes, steaming, chemicals, ultrasonic cleaners, and repolishing	HE
quench crackled	7	heated/cooled, dyed	to add color and inclusions	commonly	good - poor, depending on type of dye used		HE
rose quartz	7	no treatment	n/a	n/a	n/a	Normal Care
	7	dyed	to add color	commonly	good	Avoid heat, temperature changes, steaming, chemicals, ultrasonic cleaners, and repolishing	DYED
rutilated quartz	7	not known to be treated	n/a	n/a	n/a	Normal Care
smoky quartz	7	not known to be treated	n/a	n/a	n/a	Normal Care
	7	irradiated	to create color	usually	good		IRR
rock crystal	7	not known to be treated	n/a	n/a	n/a	Normal Care
hawk's-eye, blue tiger's eye	6.5 - 7	no treatment	n/a	n/a	n/a	Normal Care
	6.5 - 7	chemical bleaching with acid or bleaching agents	to alter color	occasionally	excellent		BL
tiger's-eye, brown	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	chemical bleaching with acid or bleaching agents	to alter color	occasionally	excellent		BL
tiger's-eye, red	6.5	heated	to change from gold to red	always	excellent	Normal Care	HE
	6.5	chemical bleaching with acid or bleaching agents	to alter color	sometimes	excellent		BL
	6.5	dyed	to alter color	sometimes	very good	Avoid sudden temperature changes, chemicals, steam and ultrasonic cleaners.	DYED
tourmalinated quartz	7	not known to be treated	n/a	n/a	n/a	Normal Care
triplets, many patterns and colors	7	assembled with natural quartz top and bottom, colored or patterned layer in between	to create new and interesting gems	occasionally	very good	Avoid solvents and ultrasonic cleaners	AS

Quartzite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
aventurine (quartzite)	6.5	no treatment	n/a	n/a	n/a	Normal Care
	6.5	dyed	to improve color	often	good to excellent	Avoid abrasives, ultrasonic, solvents and heat.	DYED
howlite white	6.5	not known to be treated	n/a	n/a	n/a	Norman Care
howlite other colors	6..5	dyed/stained	to add color	commonly	good to very good	Avoid harsh chemicals, ultrasonic cleaners, and steaming.	DYED
quartzite	6 - 6.5	no treatment	n/a	n/a	n/a	Normal Care
	6 - 6.5	dyed	to alter color	commonly	excellent	Avoid chemicals, heat and ultrasonic cleaners	DYED
	6 - 6.5	impregnated with colorless plastic	to improve appearance, and durability	commonly	good		IMP

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Rhodizite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
rhodizite	8	not known to be treated	n/a	n/a	n/a	Normal Care

Rhodochrosite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
rhodochrosite	3.5 - 4	not known to be treated	n/a	n/a	n/a	Rhodochrosite is very soft, so be mindful of scratching or chipping. Requires gentle handling.

Rhodonite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
rhodonite	5.5 - 6	no treatment	n/a	n/a	n/a	Normal, gentle handling
	5.5 - 6	dyed/stained	to add color	occasionally	poor	Normal, gentle handling. Avoid steam.	DYED

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Sapphirine
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
sapphirine	7.5	not known to be treated	n/a	n/a	n/a	Normal Care

Scapolite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
scapolite yellow	5.5 - 6	not known to be treated	n/a	n/a	n/a	Normal, gentle handling. Avoid jeweler's torch.
scapolite violet	5.5 - 6	no treatment	n/a	n/a	n/a	Normal, gentle handling. Avoid jeweler's torch.
	5.5 - 6	irradiated	to produce violet color	occasionally	poor to fair	Normal, gentle handling. Avoid jeweler's torch. When exposed to bright light color may fade.	IRR
	5.5 - 6	heated	to produce violet color	rarely	good		HE

Scheelite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
scheelite	4.5 - 5	not known to be treated	n/a	n/a	n/a	Gentle care, not suitable for jewelry

Serpentine
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
serpentine	2.5 - 6	no treatment	n/a	n/a	n/a	Serpentine is very soft, so be mindful of scratching. Avoid sudden temperature changes, chemicals, and ultrasonic cleaners. Requires gentle handling
	2.5 - 6	dyed/stained	to alter color	commonly	fair to good	Serpentine is very soft, so be mindful of scratching. Color may fade. Requires gentle handling. Avoid steam and heat, could remove dye.	DYED
	2.5 - 6	impregnated, waxed/oiled	to improve hardness and luster	commonly	good to very good	Serpentine is very soft, so be mindful of scratching. Avoid ultrasonic, chemicals, and solvents. Requires gentle handling	IMP

Shell
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
abalone (shell)	3 - 4	no treatment	n/a	n/a	n/a	Abalone is very soft, so be mindful of scratching. Avoid sudden temperature changes, chemicals, and ultrasonic cleaners. In addition to above precautions: avoid perfumes, and hairsprays. Requires gentle handling.
	3 - 4	dyed	to add color	commonly	good		DYED
	3 - 4	stabilized	prevent porosity	occasionally	fair		STB
mother of pearl (shell)	3	no treatment	n/a	n/a	n/a	Mother of pearl is very soft and porous, so avoid heat, chemicals, and ultrasonic cleaners.
	3	dyed/stained	to alter color	commonly	good to very good		DYED
	3	stabilized	to reduce porosity, to stabilize the stone	sometimes	fair to good		STB
	3	coated	to protect shell and added design	occasionally	good		CTD
shell (oyster, paua, conch, clam, scallop)	3 - 4	no treatment	n/a	n/a	n/a	Shell is very soft, so be mindful of scratching. Avoid ultrasonic, chemicals, and solvents. Requires gentle handling.
	3 - 4	dyed/stained	to alter color	commonly	fair to good		DYED
	3 - 4	stabilized	to reduce porosity, to stabilize the stone	commonly	fair to good		STB

Sillimanite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
sillimanite	6 - 7.5	not known to be treated	n/a	n/a	n/a	Normal, gentle handling.
sillimanite cat's eye	6 - 7.5	not known to be treated	n/a	n/a	n/a

Sinhalite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
sinhalite	6.5	not known to be treated	n/a	n/a	n/a	Gentle care, moderately soft.. Avoid ultrasonic cleaners.

Sodalite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
sodalite	5.5 - 6	no treatment	n/a	n/a	n/a	Normal Care
	5.5 - 6	dyed/stained	to alter color	sometimes	fair	Special Care required as dye may fade. Avoid steam and ultra sonic cleaners.	DYED

Sphene
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
sphene	5 - 5.5	no treatment	n/a	n/a	n/a	Sphene is a soft stone, so be mindful of scratching.
	5 - 5.5	heated	to create red or orange color	rarely	good		HE

Sphalerite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
sphalerite	3.5 - 4	not known to be treated	n/a	n/a	n/a	Sphalerite is a very soft stone, so be mindful of scratching. It is generally not suited for jewelry use.

Spinel
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
spinel	8	not known to be treated	n/a	n/a	n/a	Normal Care
	8	heated	to improve color and clarity	rarely	excellent	Normal Care	HE
black spinel	8	not known to be treated	n/a	n/a	n/a	Normal Care

Spodumene
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
hiddenite	6.5 - 7	no treatment	n/a	n/a	n/a	Some stones cleave or fracture easily. Wear with care.
	6.5 - 7	irradiated	to create color	rarely	poor	Gentle care. Avoid prolonged exposure to light and heat to prevent color fading. Some stones cleave or fracture easily. Wear with care. Avoid ultrasonic cleaners	IRR
kunzite pink / violet	6.5 - 7	no treatment	n/a	n/a	n/a	Gentle care. Prolonged exposure to light, especially UV and sunlight, will cause fading. Some stones cleave or fracture easily. Wear with care.
	6.5 - 7	irradiated	to improve color	commonly	fair to poor		IRR
	6.5 - 7	heated	to improve color	commonly	fair		HE
yellow, Teradora™	6.5 - 7.5	no treatment	n/a	n/a	n/a	Gentle care. Prolonged exposure to light, especially UV and sunlight, will cause fading. Some stones cleave or fracture easily. Wear with care.
	7.5	irradiated	to create color	frequently	poor	Gentle care. Prolonged exposure to light, especially UV and sunlight, will cause fading. Some stones cleave or fracture easily. Wear with care.	IRR

Sugilite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
sugilite	6	no treatment	n/a	n/a	n/a	Normal Care
	6	dyed	to improve color	occasionally	good	Avoid solvents, steam and ultrasonic cleaners.	DYED

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Taaffeite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
taaffeite	8	not known to be treated	n/a	n/a	n/a	Normal Care and handling

Topaz
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
sky, swiss, london, super	8	irradiated and annealed	to create color	almost always	excellent	Normal Care	IRR
	8	CVD coated	to add color	occasionally	fair to good	Color may be affected by polishing, recutting, ultrasonic cleaners, alcohol, and harsh chemicals.	CVD
brown, champage	8	no treatment	n/a	n/a	n/a	May fade with exposure to sunlight.
	8	irradiated	to create color	occasionally	varies		IRR
green	8	irradiated	to create color	occasionally	fair to poor	Color fades in exposure to sunlight and high heat.	IRR
	8	CVD coated	to add color	commonly	fair to good	Color may be affected by polishing, recutting, ultrasonic cleaners, alcohol, and harsh chemicals.	CVD
mystic series,pink, red, ocean, glacier, patriot, canary, champagne, orchid, dawn, teal, kiwi, etc.	8	CVD coated	to add color	commonly	fair to good	Color may be affected by polishing, recutting, ultrasonic cleaners, alcohol, and harsh chemicals.	CVD
imperial	8	no treatment	n/a	n/a	n/a	Normal Care
	8	heated	to improve color	usually	excellent	Normal Care	HE
	8	irradiated	to improve color	sometimes	variable	Avoid heat and strong light.	IRR
yellow / orange	8	irradiated	to create color	occasionally	variable	Avoid heat and strong light.	IRR
	8	heated	to improve color	usually	excellent	Normal Care	HE
white (colorless)	8	no treatment	n/a	n/a	n/a	Normal Care
	8	heated	to remove color	occasionally	excellent		HE

Tourmaline
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
indicolite	7 - 7.5	no treatment	n/a	n/a	n/a	Normal Care
	7 - 7.5	heated	to improve color	commonly	excellent		HE
	7 - 7.5	oiled/resin infused	to improve appearance	occasionally	fair to good	Avoid steaming, harsh chemicals, ultrasonic, and temperature changes.	INF
achroite, colorless	7-7.5	not known to be treated	n/a	n/a	n/a	Normal Care
cat's-eye tourmaline	7 - 7.5	no treatment	n/a	n/a	n/a	Normal Care
	7 - 7.5	oiled/resin infused	to improve clarity	occasionally	good	Avoid steaming, harsh chemicals, ultrasonic, and temperature changes.	INF
chrome tourmaline	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
dravite, brown	7 - 7.5	not known to be treated	n/a	n/a	n/a	Normal Care
green, blue	7 - 7.5	no treatment	n/a	n/a	n/a	Normal Care
	7 - 7.5	heated	to improve color	commonly	excellent		HE
	7 - 7.5	oiled/resin infused	to improve appearance	occasionally	fair to good	Avoid steaming, chemicals, ultrasonic cleaners, and temperature changes.	INF
paraiba / cuprian	7 - 7.5	no treatment	n/a	n/a	n/a	Normal Care
	7 - 7.5	oiled/resin infused	to improve clarity	sometimes	fair to good		INF
	7 - 7.5	heated	to improve color	commonly	excellent		HE
pink, red (rubellite), purple	7 - 7.5	no treatment	n/a	n/a	n/a	Normal Care
	7 - 7.5	heated	to improve color	occasionally	excellent		HE
	7 - 7.5	irradiated	to create color	commonly	excellent		IRR
	7 - 7.5	oiled/resin infused	to improve appearance	occasionally	fair to good	Avoid temperature changes, steaming, chemicals, and ultrasonic cleaners.	INF
	7 - 7.5	dyed/stained	to alter color	rarely	poor to fair	Avoid abrupt temperature changes, steaming, chemicals, and ultrasonic cleaners.	DYED
schorl	3	no treatment	n/a	n/a	n/a	Gentle handling (specimen)
yellow / orange	7 - 7.5	no treatment	n/a	n/a	n/a	Normal Care
	7 - 7.5	heated	to improve color	rarely	excellent		HE
	7 - 7.5	irradiated	to create color	rarely	very good		IRR
watermelon	7 - 7.5	no treatment	n/a	n/a	n/a	Normal Care
	7 - 7.5	heated	to improve color	commonly	excellent		HE

Tremolite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
tremolite	5 - 6	not known to be treated	n/a	n/a	n/a	Gentle care, tremolite can be brittle as well as cleave.

Turquoise
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
turquoise	5 - 6	impregnated, waxed/oiled	to improve color and luster	commonly	poor to fair	Avoid hot water, household chemicals, steam and ultrasonic cleaners.	IMP
	5 - 6	dyed/stained & stabilized	to improve color	often	poor to very good		DYED
	4 - 6	reconstructed	to make larger pieces from powder and smaller pieces	occasionally	very good		RECON
	5 - 6	stabilized	to improve durability and appearance	commonly	very good		STB
	5 - 6	Zachary Process	to improve durability and appearance	proprietary process	very good		ZPR

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Ulexite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
ulexite	2.5	no treatment	n/a	n/a	n/a	Avoid hot water, household chemicals, and ultrasonic cleaners
	2.5	coated	to improve durability	sometimes	good		CTD

Unakite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
unakite	6 - 6.5	No Treatment	n/a	n/a	n/a	Normal Care
	6 - 6.5	Impregnated	to improve durability	rarely	good	Avoid hot water, household chemicals, and ultrasonic cleaners	IMP

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Variscite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
variscite	4.5	no treatment	n/a	n/a	n/a	Normal, gentle handling. Variscite is a soft stone, so be mindful of scratching.
	4.5	impregnated with colorless plastic	to improve durability and for shaping and polishing	commonly	good	Avoid exposure to hot water, heat, steam, chemicals and ultrasonic cleaners	IMP
	4.5	dyed/stained	to improve color	often	fair to good	Avoid temperature changes, heat, steaming, chemicals, and ultrasonic cleaners.	DYED

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Witherite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
witherite	3.5	not known to be treated	n/a	n/a	n/a	Very soft and may be attacked by acids. Not suitable for jewelry.

Wulfenite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling
wulfenite	2.5 - 3	not known to be treated	n/a	n/a	n/a	Very soft , careful handling

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Zircon
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
blue	7.5	heated	to create blue	almost always	fair to good	Normal, gentle handling. Avoid abrasives and strong UV light.	HE
colorless	7.5	heated	to lighten color	almost always	fair to good		HE
green / brown	6.5 - 7.5	not known to be treated	n/a	n/a	n/a
hyacinth, pink	7.5	no treatment	n/a	n/a	n/a
	7.5	heated	to produce color	frequently	good		HE
imperial	7.5	heated	to produce color	almost always	good		HE
red	7.5	no treatment	n/a	n/a	n/a
	7.5	heated	to improve color	commonly	good		HE
yellow	7.5	no treatment	n/a	n/a	n/a
	7.5	heated	to improve color	rarely	good		HE

Zoisite
gemstone/types	hardness	enhancement method(s)	purpose	frequency	stability/durability	care and handling	on-air code
ruby - zoisite, anyolite	6.5 - 7	not known to be treated	n/a	n/a	n/a	Normal Care
	6.5 - 7	oiled	to improve color and clarity	occasionally	fair	avoid ultrasonic and harsh cleaners	O
tanzanite	6.5	heated	to improve color	almost always	excellent	Normal, gentle handling	HE
	6.5	coated	to improve color	sometimes	fair	Gentle wear, avoid ultrasonics and high heat.	CTD
green tanzanite, ocean tanzanite	6.5	no treatment	n/a	n/a	n/a	Normal, gentle handling
	6.5	heated	to improve color	frequently	excellent		HE
yellow, pink, orange, colorless (tanzanite)	6.5	not known to be treated	n/a	n/a	n/a	Normal, gentle handling
	6.5	heated	to improve color	almost always	excellent		HE

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