Apatite

saf-ahyuh r

Apatite is the name for a mineral group as well as the generic term for many phosphates, but gem-quality apatite is a special gemstone found in a beautiful variety of colors. Apatite's various colors are often due to the presence of rare earth elements or natural irradiation. Because of its wide color range, apatite has often been mistaken for many other gemstones, including topaz, tourmaline, and various beryl varieties. Particularly rare in sizes over one carat, apatite is a relatively soft gem and when used in jewelry manufacture, is often set into more protective mountings that capture light yet safely display its beauty. The long-established sources for gem-quality apatite are Brazil and Mexico, but more recent African discoveries have thrust it into the spotlight once again.

Apatite Polished
Apatite Classification
Common Name Apatite
Species Apatite
Apatite Optical Properties
Transparency Transparent - Translucent
Dispersion Strength: Weak Fire Value: 0.013
Refractive Index 1.634-1.638
Tolerance:(+0.012/-0.006)
Birefringence 0.002-0.008
Optic Character Uniaxial
Optic Sign Negative
Polariscope Reaction Doubly Refractive (DR)
Fluorescence SWUV: Variable
LWUV: Variable
Pleochroism Dichroic, strong blue and yellow (in blue gems) and in other colors, weak to very weak tones of bodycolor
Apatite Characteristic Physical Properties
Hardness 5
Streak White To Yellow-Gray
Specific Gravity 3.130-3.230 Range:+/- 0.05
Toughness Fair
Inclusions Apatite is a type II stone. The stones are often found with natural inclusions, healing cracks and hollow tubes.
Luster Vitreous
Stability Fair
Fracture Conchoidal, Uneven
Cleavage Poor, in two directions
Apatite Chemistry & Crystallography
Chemical Name calcium phosphate with fluorine, chlorine or hydroxyl group
Chemical Formula Ca5(PO4)3(F,OH,Cl)
Crystal System Hexagonal
Chemistry Classification Phosphate

Apatite Colors

  • Colorless Apatite Colorless

Apatite Spectra

Apatite Spectra
APATITE Greenish blue

Color due to color centers and rare earth elements. The rare earth neodymium is generally present to some extent in apatite. The spectrum can consist of groups of very fine lines in the blue, green and yellow areas but the number and strength of the lines is not always proportional to the depth of color in the gemstone. Here only the group of fines in the yellow is seen with a vague lie in the green.

Apatite Spectra
APATITE

Color due color centers and rare earth neodymium. An almost continuous spectrum but often as here a group of fine lines in the yellow due to the rare earth neodymium is seen subduing the transmission resulting in an almost colorless stone.

Apatite Spectra
APATITE

Color due to neodymium The main feature seen in most specimens of apatite can be seen here as a moderate broad band centered at 580nm. which, In some stones, may be better resolved as a group of five fine lines. An indication of another group of weak lines can be seen in the green after which strong absorption takes over at about 510nm.

Jewelry Television acknowledges the significant scientific contributions of John S Harris, FGA to the study of gemstone spectra and with deep appreciation to him, acknowledges the use of his images and related notes about gemstones and their spectra in the educational materials on this website.

Alternate Names

Fluorapatite, Asparagus Stone, Moroxite

Countries of Origin

Tanzania, United Republic Of; Colombia; Myanmar; Afghanistan; Czechia; Sri Lanka; Dominican Republic (the); Madagascar; Kenya; French Polynesia; India; Canada; Mozambique; Pakistan; Morocco; Unknown; China; Namibia; Russian Federation (the); Brazil; Mexico; Zimbabwe; Nigeria

History

The Caribbean blues and greens we associate with gem-quality apatite give it cool, easy appeal. Even the yellow shades have undertones that resonate on the cool side of the color wheel. The variety of colors of apatite make it a desirable stone for jewelry. It's a 5 on the Mohs scale and should be treated with care and as a special-occasion stone. Consider it like a fine gown, store it carefully and wear it when the event calls for something truly special. Gem-quality apatite is a unique stone whose various colors are often due to the presence of rare-earth elements or natural irradiation. Apatite cat's-eye is highly sought-after and seldom found. It exhibits chatoyancy that is best displayed in a cabochon cut. Consider created apatite as an alternative to the mother-earth stone. It's hard, very wearable and perfect for those who want to enjoy its enticing colors every day.

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More About Apatite

Some people believe that apatite is an inspirational stone that contributes to learning. There are many qualities attributed to it by those who subscribe to the metaphysical. One of our favorites is the idea that apatite can suppress hunger. We subscribe to believe in the qualities of beauty and color - apatite delivers!

Apatite Gemstone

Sisk Gemology Reference

Showcasing 200 gemstones in over 1,000 pages and accompanied by more than 2,000 photos, The Sisk Gemology Reference is a must-have in every collector’s library. Each comprehensive, three-volume set features state-of-the-art photography, detailed illustrations, and scientifically precise descriptions to create an entrancing experience for gemstone amateurs and afficionados alike.

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Optical Phenomena

Cat's-Eye

The term cat's eye, or chatoyancy, is used to describe a phenomenal optical property in gemstones, in this case apatite. The effect, when present, appears as a bright, narrow slit similar to the pupils in the eyes of your favorite feline. This phenomenon is caused by parallel fibrous or needle-like inclusions that interfere with the passage of light throughout the crystal, scattering and reflecting light back to the viewer as a thin line.Chatoyancy is the only known phenomenon seen in apatite. The most common colors for cat's eye apatite are bluish green, green and yellow. Brazil and Sri Lanka are the principal sources of chatoyant apatite, although it may also be found in Madagascar and Tanzania.

Cat's-Eye Apatite
Cat's-Eye Classification
Common Name Cat's-Eye
Cat's-Eye Optical Properties
Pleochroism Unobservable
Cat's-Eye Characteristic Physical properties
Inclusions Apatite is a type II stone. Fairly well defined chatoyant band that is made up of finer tubular inclusions than cat's-eye tourmaline.
Tim Matthews

Author

Tim Matthews

Tim Matthews is President and Chief Executive Officer of Jewelry Television® (JTV), as well as a member of the company's Board of Directors. He oversees and leads all aspects of the company's powerful omni-digital retail platform that uniquely specializes in fine jewelry and gemstones. His passion for business and gemstones has led him to become a recognized expert in the field of gemology. He is a life member of the Gemmological Association of Great Britain (Gem-A) and has earned Gem-A's highest degrees, the Gemmology (FGA) and Diamond (DGA) diplomas. He is also a Graduate Gemologist (GG) of the Gemological Institute of America (GIA) and has also completed GIA's Graduate Diplomas in Diamonds, Colored Stones and Pearls. Under his leadership, JTV has become the leader in the sourcing and selling of color gemstones and jewelry.

This page was created on June 27, 2014.

This page was last edited on October 24, 2019.