Gemstone Treatment Guide


Lists and explains each treatment or enhancement used on gemstone materials and pearls sold by Fire Mountain Gems and Beads®.

We use the following symbols to designate natural, enhanced, synthetic and imitation (manmade) gemstones. All of the symbols used are those described by the American Gem Trade Association (AGTA), of which we are charter members. It is the practice of Fire Mountain Gems to disclose all treatments (also known as enhancements), to the gems we sell (with the exception of normal cutting and polishing). We also disclose the method of treatment, if known. This disclosure will appear both on the stone's advertising and on the stone's invoice. For the benefit of your customer and your company, we strongly suggest that you follow these guidelines when you sell gemstones and jewelry.

(ASBL) - Assembled: Products made of multiple layers or combinations of manufactured and/or natural materials joined together. Example: opal triplets.

(B) - Bleaching: The use of chemical agents to lighten or remove a gemstone's color.

(C) - Coating: Surface treatments to improve appearance, provide color or other special effects.

(D) - Dyeing: The introduction of coloring matter into a gemstone to give it new color, intensify present color or improve color uniformity.

(E) - Enhanced: This indicates that this type of gemstone is routinely enhanced. Since many treatments are difficult or impractical to prove definitively, the approach taken in our printed materials and invoices is to assume, unless otherwise indicated, that such treatment has been done to the particular gemstone material being described. If the particular type of treatment is known, that treatment symbol will be stated, rather than the "E" symbol.

(F) - Filling: As a by-product of heat treatment, this is the presence of solidified borax or similar colorless substances which are visible under properly illuminated 10x magnification.

(G) - Gamma/Electron Irradiation: The use of gamma and/or electron bombardment to alter a gemstone's color, which may be followed by a heating process.

(H) - Heating: The use of heat to effect desired alteration of color, clarity and/or phenomena.

(I) - Infilling: The intentional filling of surface-breaking cavities or fractures usually with glass, plastic, opticon with hardeners and/or hardened foreign substances to improve durability, appearance and/or add weight.

(IMIT) - Imitation: Manmade products, fabricated in such materials as glass, ceramic or plastic designed to imitate or resemble the appearance, but not duplicate the characteristic properties, of a natural gemstone.

(L) - Lasering: The use of lasers and chemicals to reach and alter inclusions in diamonds.

(MM) - Manmade: Fabricated products.

(N) - Natural: Stones which are not currently known to be enhanced.

(O) - Oiling/Resin Infusion: The intentional filling of surface-breaking cavities with a colorless oil, wax, natural resin or unhardened manmade material into fissured transparent/translucent gemstones to improve appearance.

(R)- Irradiation: The use of neutrons, requiring an environmental safety release from the NRC, with the combination of any other bombardment and/or heat treatment to alter a gem's color.

(S) - Stabilization (Bonding): The use of a colorless bonding agent (commonly plastic) with a porous gemstone to give it durability and improve appearance.

(SYN) - Synthetic: These are manmade materials which have essentially the same optical, physical and chemical properties as a naturally occurring counterpart.

(U) - Diffusion: The use of chemicals in conjunction with high temperatures to produce color and/or asterism (star-like) inclusions.

(W) - Waxing/Oiling: The impregnation of a colorless wax, paraffin and/or oil in porous opaque gemstones to improve their appearance.

Additional Notes: If you resell gems obtained from us, or any gems for that matter, it is your responsibility to provide all information pertinent to the treatment of a gemstone at the time of sale. If a stone is manmade, it is the seller's responsibility to disclose that fact. This information is required by the Federal Trade Commission (FTC).

Failure to identify treatment of natural gemstones when present, is an unfair trade practice. Such information is required at each and all levels of jewelry commerce. Failure to inform buyers could subject violators to civil as well as administrative remedies. Anyone who is uncertain about these requirements may write the American Gem Trade Association, 3030 LBJ Freeway, Suite # 840, Dallas, TX 75234.

Customer Comments

We would like to share some of the customer comments we received in response to the article "Gemstone Treament Guide," featured in a newsletter. Please keep in mind that the comments expressed below are those of our customers and do not reflect the views of Fire Mountain Gems and Beads.

''Thank you for printing the explanations of the treatments used on gems, pearls and stones. It will be useful in making, selling and wearing jewelry."
- Susan

''Thank you for presenting the AGTA manual. I have printed it and will make a file to carry with me to my sales locations. I like to be informed of all aspects associated with the gemstones I work with and sell."
- Nina

''Your article on gemstones was really interesting and insightful. I really enjoyed reading it. Thank you very much for sending it out. "
- Beverly

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