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Gemstone Enhancement

Some gemstone material may have received prior treatment to change or enhance color.
We do not treat or enhance any gem material.

"This manual sets forth proper methods to comply with the FTC Guides. With the exception of the normal fashioning (cutting and polishing) of a diamond and other gemstone, it is the seller's responsibility at the time of the sale to provide all information pertinent to the enhancement and alteration of a natural gemstone. If the stone is not natural, it is also the seller's responsibility to disclose that fact. This information is required by the Federal Trade Commission (FTC)."

"Failure to identify enhancement/alteration of natural gemstones, when present, is an unfair trade practice."

Definitions and Gemstone Enhancement Codes:

Enhancement is defined as any process other than cutting and polishing that improves the appearance (color/clarity/phenomena), durability, or availability of a gemstone. The following codes have been developed to express any Enhancements that have been done to a gemstone.

Symbol Definition

A
Indicates either a gemstone that is not currently known to be enhanced or one that is so rarely enhanced that to give it an "E" symbol would mislead the public.

        Example: Amethyst is rarely known to be treated.



E
Indicates that this gemstone is routinely enhanced



N
Indicates this particular gemstone has received no enhancement and the seller will guarantee this.



B

Indicates that Bleaching of the gemstone has been done. Bleaching is the use of chemicals or other agents to lighten or remove a gemstone's color.

        Example: 'Blonde Tigereye" is enhanced in this manner



C
Indicates that a Coating has been used as a surface treatments such as waxing, lacquering, enameling, inking, foiling, or sputtering of films to improve appearance, provide color or add special effects.



D
Indicates that Dyeing has occurred. Dyeing is the introduction of coloring matter into a gemstone to give it new color, intensify present color or improve color uniformity.

        Example: Agate is sometimes enhanced in this manner.



F
Indicates the gemstone has had Filling or Infilling or Stabilizing of some form. This is the filling of surface-breaking cavities or  porous gem material with colored or colorless glass, plastic or other hardened material to improve appearance, durability, and/or weight.

        Example: Turquoise is commonly enhanced in this manner.



G
Indicates the gemstone has undergone some form of Gamma or Electron Irradiation. This is the use of gamma and/or electron bombardment to alter a gemstone's color. May be followed by a heating process ("H").

        Example: Blue Topaz is commonly enhanced in this manner.



H
Indicates the stone has been heated to effect desired alteration of color, clarity, and/or phenomena.
 
        Example: Sapphire is commonly enhanced in this manner.
        Example: Citrine is commonly enhanced in this manner.



L

Indicates the gemstone has undergone the use of a laser and chemicals to reach and alter inclusion

        Example: Diamond is commonly enhanced in this manner



O

Indicates the introduction of a colorless oil, wax, natural resin, or unhardened man-made materials into fissured or porous gemstones was made to improve appearance.

        Example:  commercial grade Emerald is commonly enhanced in this maner.



R
Indicates the gemstone has undergone Irradiation. This is the use of neutron or a combination of neutron with any other bombardment to alter a gemstone's color. May be followed by a heating process ("H").

        Example: Blue Topaz is commonly enhanced in this manner



U
Indicates the gemstone has undergone Diffusion which is the use of chemicals in conjunction with high temperatures to produce a relatively shallow layer of color and/or asterism-producing inclusions.
 
       Example: Diffusion treated Sapphire is enhanced in this manner.



For more information regarding gem enhancement you can contact the AGTA for an infomative brochure entitled - Gemstone Enhancements What you should know.  AGTA, P.O. Box 420643, Dallas, TX 75342-0643

Gemstone Enhancement: History, Science and State of the Art, Second Edition, 1994,
by Kurt Nassau, published by Butterworth/Heineman