Emerald

saf-ahyuh r
May Birthstone

Few gemstones command as much desire and passion as emerald. Since antiquity, emerald's rich "green fire" has symbolized eternal spring and immortality. Long shrouded in myth and lore, it has reigned as the supreme green gem with no indication that its position will ever change. The favorite of Cleopatra, Spanish Conquistadors and today's Red Carpet, wars have waged over this treasured stone. In the 1st century AD, Roman historian Pliny the Elder wrote that "nothing greens greener" than emerald a sentiment that continues today, as it remains one of the most sought-after gems on the market. The beautiful green hues of this beryl variety, combined with its rarity, make it one of the world's most valuable gemstones.

Emerald Polished
Emerald Classification
Common Name Emerald
Species Beryl
Emerald Optical Properties
Transparency Transparent - Translucent
Dispersion Strength: Weak Fire Value: 0.014
Refractive Index 1.577-1.600
Tolerance:(+0.017/-0.017)
Birefringence 0.005-0.009
Optic Character Uniaxial
Optic Sign Negative
Polariscope Reaction Doubly Refractive (DR)
Fluorescence SWUV: Inert to weak orangy red to red
LWUV: Inert to strong orangy red to red
CCF Reaction Some appear pink or red; not diagnostic.
Pleochroism Dichroic, moderate to strong, varying shades of body color
Emerald Characteristic Physical Properties
Hardness 7.5
Streak White
Specific Gravity 2.670-2.900 Range:0.18/-0.05 Typical:2.72
Toughness Poor
Inclusions Emerald is a type III clarity stone. 3-phase inclusions typical of Colombian material. 2-phase inclusions usually found in stones from India. Tremolite needles are typical of Zimbabwe stones. Actinolite needles can be found in Siberian stones. Emeralds sometime have tube-like and bamboo-like inclusions, liquid and fingerprint inclusions, calcite, pyrite, mica, needles and amphibole inclusions.
Luster Vitreous
Stability Fair
Fracture Conchoidal
Cleavage Poor, in one direction
Emerald Chemistry & Crystallography
Chemical Name beryllium aluminum silicate
Chemical Formula Be3Al2(SiO3)6
Crystal System Hexagonal
Chemistry Classification Silicate

Emerald Colors

  • Green Emerald Green

Emerald Spectra

Emerald Spectra
EMERALD GILSON FLUX SYNTHETIC E RAY

As the e ray is isolated the more bluish green color is seen in the body color of the stone and the spectrum reacts accordingly. The main absorption band has moved further to the long wave side to obscure the line at 637nm. The line at 662nm. and the doublet at 680/683nm. are present but not as strong as in deeper colored emeralds. The line in the blue at 477nm. is not present on this ray.

Emerald Spectra
EMERALD LENNIX Lab Created (Unpolarized)

Color mainly due to chromium. The absorption spectra is essentially the same for that of natural Emerald.

Emerald Spectra
EMERALD LENNIX Lab Created  (ω ray)

The o ray spectrum is typical of most emeralds of this color saturation with the feature of the line in the blue at 477nm. although in this case a little difficult to detect as absorption sets in around this point. The line in the orange- red at 637nm. has strengthened and the doublet is weaker as the o ray assumes its more yellowish green color.

Emerald Spectra
EMERALD LENNIX Lab Created (ε-ray)

Color mainly due to chromium. The absorption spectra is essentially the same for that of natural Emerald. The line at 637nm has now disappeared, covered by the main absorption band which has moved further to the long wave side allowing the line at 662nm. to be seen. The line sometimes seen at 646 nm. remains hidden by the main band. The shift in absorption and the absence of the line in the blue accounts for the more bluish green of the e ray.

Emerald Spectra
EMERALD GILSON FLUX SYNTHETIC unpolarized

Color mainly due to chromium. As the color saturation becomes less, so does the strength of absorption. The main feature is the central absorption band is weaker and narrower and the other lines are noticeably weaker.

Emerald Spectra
EMERALD GILSON FLUX SYNTHETIC O RAY

The dichroism in this stone is more pronounced as the o ray assumes it's more yellowish green color. The o ray spectrum is typical of most emeralds of this color saturation with the feature of the line in the blue at 477nm. but rather weak and not easily detected. The central area of absorption has strengthened and widened. Other lines are weaker.

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.

Cuts Above

Jardin, the French word for "garden," is the name used in the industry to refer to inclusions in emeralds. Because of the nature of this type III gemstone, it is accepted that emeralds are commonly included. Rather than detracting from a stone's value, those jardin are viewed as an easy way to distinguish a natural emerald from a synthetic. It is also understood that nearly all emeralds have been treated to improve their clarity.

Countries of Origin

Tanzania, United Republic Of; Colombia; Afghanistan; United States of America (the); Cambodia; Sri Lanka; Zambia; Thailand; Bolivia (Plurinational State of); India; Austria; Pakistan; Unknown; China; Namibia; Russian Federation (the); Brazil; Mexico; South Africa; Australia; Chile; Ethiopia

History

Emerald is the stone that sets the standard by which all green gemstones are measured. The most-famous member of the beryl family, emerald is prized for its variety of greens, often with secondary blue or yellow hues. From deep, rich greens to the palest, springtime pastels, emerald has the perfect color for the green-lover in you. Emeralds get their green from chromium, vanadium, or both. There are other elements that color beryl green, but only those colored by chromium and vanadium are classified as emeralds. In his epic work, Natural History, the Roman historian Pliny the Elder stated of emeralds, "The sight of no other color is more agreeable... because nothing greens greener."\

Care

Emeralds are also known for their jardins, French for "gardens" - inclusions intrinsic to each stone and which make every stone unique. Almost all emeralds are oiled. Treat your emerald like the special stone it is - no harsh chemicals, steam, or sonic cleaning. Warm sudsy water will keep it looking its best.

Shop Emerald

Related Videos

More About Emerald

To the ancient Romans, emerald symbolized the reproductive forces of nature. To the early Christians, emerald represented resurrection. No stone with the glory of color that is emerald could be thought to be less than magical! According to Marbode, writing in the 11th century, "emerald improves memory, makes its owner eloquent and persuasive, and brings him joy." We can't confirm eloquence or persuasion... but we can certainly affirm joy!

Emerald 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.

Shop Now

 

Pattern

Trapiche

Trapiche emeralds hail exclusively from the emerald mines in the Boyac region of Colombia, and are so named because their patterns resemble the spoked wheels of the heavy gear locals use to grind sugar cane. Extremely limited in supply, trapiche emeralds are perhaps the rarest of all "pattern" gemstones. Their six distinct "spokes" are caused by the presence of the mineral inclusion lutite. As the hexagonal emerald crystal grew, it pushed the lutite towards the center of the crystal and then radiated out in the six directions of the emerald crystal. A truly remarkable feat, compliments of Mother Nature!

Trapiche Emerald
Trapiche Classification
Common Name Trapiche
Trapiche Optical Properties
Refractive Index 1.560-1.570
Fluorescence SWUV: Inert
LWUV: Inert
Pleochroism Dichroic, weak to moderate, varying shades of body color

Creation Method

Lab Created Overgrowth Hydrothermal

One of the most popular methods for creating emerald is the hydrothermal process, which uses heat and pressure to imitate natural conditions deep in the earth that formed natural gems. Nutrients are dissolved in a water solution with synthetic crystals forming as the solution cools. Synthetic emeralds offer you the best of both worlds. You get the beauty of a beloved, rare gemstone, but at a budget-friendly price!

Lab Created Overgrowth Hydrothermal Emerald
Lab Created Overgrowth Hydrothermal Classification
Common Name Lab Created Overgrowth Hydrothermal
Lab Created Overgrowth Hydrothermal Optical Properties
Refractive Index 1.566-1.570
Fluorescence SWUV: Weak to moderate red in the synthetic layer
LWUV: Moderate to strong red in the synthetic layer
CCF Reaction Often a bright red; not conclusive
Lab Created Overgrowth Hydrothermal Characteristic Physical properties
Toughness Good

Hydrothermal

Hydrothermally grown synthetic emeralds crystallize slowly out of a solution (a mix of water and dissolved elements) that has been exposed to heat and pressure similar to the conditions on Earth under which the natural gem mineral grows. Synthetic gems have the same chemical, optical, and physical properties of their natural counterparts, but are a more cost-effective alternative to a natural gem.

Hydrothermal Emerald
Hydrothermal Classification
Common Name Hydrothermal
Hydrothermal Optical Properties
Refractive Index 1.571-1.584
Tolerance:(+0.007/-0.002)
Birefringence 0.004-0.008
Fluorescence SWUV: Variable
LWUV: Variable
CCF Reaction Sometimes bright red; not conclusive
Hydrothermal Characteristic Physical properties
Specific Gravity 2.63
Stability Good

Sandwich Hydrothermal

Synthetic refers to a man-made material with a natural counterpart. The synthetic crystal replicates the chemical, optical and physical properties of the natural crystal with little or no variation. One of the most popular methods for creating synthetic emerald is the hydrothermal process, which uses heat and pressure to imitate natural conditions deep in the earth that formed natural gems. Nutrients are dissolved in a water solution with synthetic crystals forming as the solution cools. Synthetic emeralds offer you the best of both worlds. You get the beauty of a beloved, rare gemstone, but at a budget-friendly price!

Sandwich Hydrothermal Emerald
Sandwich Hydrothermal Classification
Common Name Sandwich Hydrothermal
Sandwich Hydrothermal Optical Properties
Refractive Index 1.575-1.581
Birefringence 0.004-0.004
Fluorescence SWUV: Moderate to strong red
LWUV: Moderate to strong red
CCF Reaction Often a bright red; not conclusive
Sandwich Hydrothermal Characteristic Physical properties
Stability Good

Flux Growth

One method of synthesizing emeralds is called flux growth. During the flux growth process, flux, a substance that reduces the melting point of surrounding material, is combined in a metal-lined crucible with the elements that make up emerald. The crucible is heated until its contents are liquid and then it is allowed to cool very slowly. As cooling continues, the gem mineral crystallizes from the solution. Flux grown synthetic gems can take up to a year to grow to a facetable size, but the exceptional clarity of these gems is well worth the wait! Synthetic gems have the same chemical, optical, and physical properties of their natural counterparts, but are a more cost-effective alternative to a natural gem.

Flux Growth Emerald
Flux Growth Classification
Common Name Flux Growth
Flux Growth Optical Properties
Refractive Index 1.562-1.569
Tolerance:(+/-0.003)
Birefringence 0.003-0.005
Fluorescence SWUV: Variable
LWUV: Variable
CCF Reaction red
Flux Growth Characteristic Physical properties
Specific Gravity 2.66
Stability Good

Enhancement

Fractured-Filled

Fracture filling is the filling of surface-breaking cavities or fissures with highly refractive colorless glass. This process may improve the appearance, durability and/or weight of the emerald.

Fractured-Filled Emerald
Fractured-Filled Classification
Common Name Fractured-Filled
Fractured-Filled Optical Properties
Fluorescence SWUV: Variable
LWUV: Variable
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.