REPORT VERIFICATION # ________________________

Online beginning April 15, 2016 

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COUNTRY OF ORIGIN EXPLANATION

At GIA and other major laboratories only ruby, sapphire, emerald and paraiba tourmaline qualify for a colored stone origin report. In certain markets, such as Indonesia; customers want a country of origin determination for any gemstone. At DGL all gemstones other than ruby, sapphire, emerald and paraiba tourmaline take into account the current international gemstone market, comparison of reference material and published material, and standard gemological analysis to arrive at a country of origin opinion. Note: the chemistry altering impact of high temperature enhancements and an increasing number of new locations has complicated origin analysis.

ROYAL BLUE AND PIGEON'S BLOOD EXPLANATION

At DGL we follow the the definition put forth by GRS Laboratory (read more). Gubelin and SSEF have a different criteria. Especially in regards to heat treatment (read more).

ANALYSIS OF MOUNTED DIAMONDS AND GEMSTONES

Even visual impairments such as metal parts surrounding gemstone(s) allow DGL gemologists to provide detailed information but perhaps not as accurately as in an un-mounted situation. In these cases the words "approximate" and "estimate" are used as descriptors. Ultimately some pieces may require un-mounting if the style or makeup prevents our gemologists from performing the scientific tests necessary for meaningful assessment. Reversing or modifying lab results when stones are unmounted are known to happen (read more here, here and here). Because all laboratories express their results as an opinion, many customers receive analysis from more than one lab (read more).

TREATMENT CODES

A-Jade

No treatment. Natural jadeite that has not been acid bleached or filled with a polymer

AS

Assembled. The assembling of natural with natural and/or man-made parts to improve durability or appearance. Examples: opal doublet, mabe pearl, quartz triplet and inlays.

B

Bleached. The use of heat, light, and/or chemicals or other agents to lighten or remove a gemstone's color. This is sometimes accompanied by subsequent dying and/or impregnating to stabilize the resulting color. Examples: cultured pearl, golden coral, B-jade.

B-Jade

Natural jadeite that has been acid bleached to remove stains and impurities and is then filled with a polymer, usually with color added, to improve translucency and color.

BLKND

Blackened. The process of darkening the bottom of a piece of amber to alter the color. Blackening the bottom of golden amber creates a greenish color.

COMP

Composite. Composed of disparate pieces of various gem materials that are bonded together. A dyed or bonding agent may impart color. Components may all be one type of gem material or mixed varieties. Examples: mosaic turquoise, rainbow calsilica(man-made composite).

C

Coated. The use of such surface enhancements as lacquering, enameling, inking, foiling, chemical vapor deposition(cvd) or sputtering of films to improve appearance, improve durability, provide color or add other special effects. Examples: diamond, opals(black coating on back,black star sapphires, mystic topaz, tanzanite.

C-Jade

Natural jadeite that has been acid bleached to remove stains and impurities and is then filled with a colored polymer to change and/or improve translucency and color.

D

Dyed. The introduction of coloring matter into a gemstone to give it new color, intensify existing color or improve color uniformity. Examples: dyed chalcedony, pearl, coral, lapis, emerald, ruby, quartz, jade.

FF

Fracture Filled. The filling of surface-breaking cavities or fissures with highly refractive colorless glass. This process improves apparent clarity. Example: diamond, ruby, emerald.

H

Heated. The use of heat to alter color, clarity, and/or phenomena. No residues present.  Examples: amethyst, citrine, ruby, sapphire, tanzanite, aquamarine, demantoid garnet, amber, topaz, zircon,tourmaline, carnelian.

H(a)

Flux healed (moderate). During heat enhancement, fluxes may be used to melt the original gemstone fissure walls together so as to partly heal the natural fissures. Clarity and/or color are permanently enhanced.  H(a) indicates small residues within fissures only. Example: ruby, sapphire.

H(be)

Enhanced by heat and Beryllium. Clarity and/or color are enhanced by heat and diffusion of light elements such as Beryllium. Be-treatment produces a considerable color enhancement. Note: if a padparadsha colored sapphire has been beryllium treated, it will not be described as padparadsha on the report.

H(c)

Flux healed (significant). During heat enhancement, fluxes may be used to melt the original gemstone fissure walls together so as to partly heal the natural fissures. Clarity is permanently enhanced. H(c) indicates residues within fissures identifiable with 10x magnification. Example: ruby, sapphire.

H(d)

Glass filled. Heat-treated and filled with a colored foreign solid substance (including lead glass). Special care required when handling. Also known as Composite Ruby, Hybrid Ruby, Synthetic Glass/Treated Ruby. Because of the extreme level of enhancement some labs regard this material as man-made and not an enhanced natural gemstone.

H(dc)

Cobalt Glass filled sapphire. Heat-treated and filled with a cobalt and lead substance to enhance color and clarity. The Pb+Co sapphires are not stable and require special care as they may be damaged when soaked in detergent and acids or during jewelry repairs.

H(uc)

Cobalt diffused Spinel. New type of treatment of spinel involving heat-treatment and Cobalt-diffusion.

HPHT

HPHT annealed. The use of high heat and pressure combined to affect desired alterations of color. Example: colored and near-colorless diamonds.

L

Lasered. The use of a laser and chemicals to reach and alter inclusions. Example: diamond.

LPLT

Autoclaved Treated. A method of applying moderately low heat and pressure. Commonly done with copal to create green amber. This treatment simulates a rapid aging process, making the stability of copal comparable to amber while also creating a green color.

MM

Man-Made is synonymous with simulant, substitute or imitation. A simulant only mimics the appearance of another more expensive gemstone. A simulant usually indicates a man-made material, but may be natural. Examples: red glass (ruby simulant), white YAG (diamond simulant).

O

Oiled. The filling of surface-breaking fissures with a colorless oil, wax, resin, or other colorless substance except glass or plastic, to improve the gemstone's clarity. The amount of enhancement is described as minor, moderate or significant. Example: emerald and any stone with surface reaching fissures.

O(d)

Dyed Oil. The filling of surface-breaking fissures with a colored oil, wax, resin, or other colored substance except glass or plastic, to improve the gemstone's color and clarity. The amount of enhancement is described as minor, moderate or significant. Example: emerald and any stone with surface reaching fissures.

POLY

Polymer Filled. The filling of surface-reaching fissures with colorless polymers to improve clarity. Includes the proprietary Excel™ treatment as well as other semi-permanent processes which allow for ease of care and normal cleaning without degrading the appearance of the stone. The latest generation of treatment technology, these processes bring out the natural beauty of the emerald while minimizing care concerns. The amount of enhancement is described as minor, moderate or significant. Example: emerald.

POLY(d)

Dyed Polymer Filled. The filling of surface-reaching fissures with colored polymers to improve color and clarity. Includes the proprietary Excel™ treatment as well as other semi-permanent processes which allow for ease of care and normal cleaning without degrading the appearance of the stone.The amount of enhancement is described as minor, moderate or significant. Example: emerald.

PRS

Pressed. The process of partially melting and pressing together smaller pieces or powders of natural resins such as amber and copal. Pressed amber retains the same properties of unpressed amber. In addition, it usually improves clarity and may have color added.

R

Irradiated. The use of neutron, gamma, ultraviolet and/or electron bombardment to alter a gemstone's color. The irradiation may be followed by a heating/annealing process. Examples: blue topaz, colored diamonds.

RECON

Reconstituted. Small particles of natural material compressed and bonded into a larger whole. . Example: some turquoise.

SM/SA

Smoke and Sugar Treatment of Opal. These are the two most common carbonizing methods. In the sugar treatment process, the opals are heated in a saturated sugar solution. The opal material absorbs this sugar. It is then immersed in concentrated sulfuric acid. A chemical reaction takes place between the sugar and acid, leaving only the remaining carbon. The carbon residues of smoke and sugar treatment darkens the background color of the precious opal which enhances the play-of-color and makes the stone appear brighter. A third less common treatment is to soak the opal in automotive oil or other material and then heat the stone to affect carbonization within the microscopic voids of the opal.

STB

Stabilized. Not to be confused with reconstituted turquoise, the more valuable stabilized turquoise is solid, whole turquoise that has been filled(impregnated) with colorless polymer to reduce porosity, providing a polished finish that protects the stone against breakage and discoloration. The color always improves as a result of the treatment, but some processes may add additional dyes as well. When color is added, this is additionally disclosed.

STB(d)

Dyed Polymer Stabilized. Turquoise that has been filled(impregnated) with colored polymer to reduce porosity and improve color.

SYN

The term synthetic is used to describe a lab-created gemstone that has a natural counterpart. Synthetic gemstones have the same chemical, optical, and physical properties as those occurring in nature. Examples: synthetic sapphire, synthetic alexandrite.

U

Diffused. Surface diffusion. The outside-in diffusion of elements via high-temperature heat treatment to produce a layer of color and/or asterism. Examples: diffused star sapphire,andesine-labradorite,

W

Waxed. The impregnation of a colorless wax or paraffin in porous gemstones to improve their surface appearance. Examples: coral, amazonite.