THE BRAZILIAN CONNECTION - Gemstones & Gemstone Jewelry

Gemstone Enhancements

Many people confuse gemstone enhancements with the terms synthetic, man-made, lab-grown or other processes which involve the creation of materials not found in the earth. gemstones are those created by processes. Man-made, laboratory grown or synthetic materials are those created by non- processes. Enhancements are additional treatments performed on , or synthetic materials to generally improve their appearance. A gemstone that is enhanced is still considered a gemstone.  The term enhancement is defined as any treatment or process other than cutting and polishing that improves the appearance (color/clarity/phenomena), durability, value or availability of a gemstone. In today’s gem marketplace, many gemstones have been enhanced by a variety of methods. Such processes may range from simple heating (such as with tanzanite) to high-tech irradiation (such as blue topaz).   While many enhancements are currently undetectable, we do our best to provide all the information you need for informed buying decisions. The guidelines used are those of the AGTA and are the most stringent in the industry.  Some gemstone enhancements are less stable than others, meaning that the appearance of a gem may change with time.   A gemstone enhancement is considered stable as long as the gem does not change in appearance (color and/or clarity) under normal wear, cutting, cleaning, repair or display conditions. Gemstones can be divided into three basic enhancement categories.

• Not Enhanced (N)
  The “N” symbol is used to indicate one of two situations. First, there are certain gemstones that are not currently known to be enhanced (alexandrite, some garnets, etc.). Second, the “N” symbol may also be used for a gem where it can be proved via gemological or other means that a gem has not been subjected to any enhancement. When you see the “N” symbol with a gemstone description,  the gem in question is unenhanced.
• Normally Enhanced (E)
  The “E” symbol is used for gemstones that are routinely enhanced. Since many enhancements are difficult or impractical to prove definitively, unless otherwise indicated, our approach is to assume that such enhancements have been applied to that particular gemstone. This assumption is made to protect both buyer and seller. If a more specific method of enhancement is known, then the specific enhancement code will be used.
• Nontraditional Enhancements (T)
  For gemstones not covered by the “N” and “E” symbols, a code covering the specific gemstone enhancement will be listed.

Symbols for Specific Forms of Enhancement

• B = Bleaching: The use of heat, light and/or chemicals or other agents to lighten or remove a gemstone's color. This is often accompanied by subsequent dying and/or impregnation. Example: bleached cultured pearl; bleached/impregnated jadeite (‘B-jade’)
• C = Coating: The use of such surface enhancements as lacquering, enameling, inking, foiling, or sputtering of films to improve appearance, provide color or add other special effects. Example: coated diamond
• D = Dyeing (staining): The introduction of coloring matter into a gemstone to give it new color, intensify existing color or improve color uniformity. Example: dyed green jadeite
• F = Filling: The filling of surface-breaking cavities or fissures with colorless glass, plastic, or some similar substance. This process will improve durability, appearance and/or add weight. Example: ruby
• Fh = Flux healing: During heat enhancement, fluxes (or heat alone) may be used to heal fractures/fissures which were formerly open. The process dissolves the walls of the fractures and redeposits the molten gem material, healing the fractures closed. Example: ruby (particularly that from Möng Hsu, Burma)
• H = Heating: The use of heat to alter color, clarity, and/or phenomena. Example: Ruby, sapphire, tanzanite, aquamarine, demantoid garnet
• I = Impregnation: The impregnation of a porous gemstone with a colorless agent (usually plastic) to give it durability and improve appearance. Example: Stabilized turquoise
• L = Lasering: The use of a laser and chemicals to reach and alter inclusions. Example: diamond
• O = Oiling/Resin Infusion: The filling of surface-breaking fissures with a colorless oil, wax, resin or other colorless substances, except glass or plastic, to improve the gemstone’s appearance. Example: emerald
• R = Irradiation: The use of neutrons, gamma, ultraviolet and/or electron bombardment to alter a gemstone’s color. The irradiation may be followed by a heating process.
  Example: blue topaz
• U = Lattice (‘bulk’ or ‘surface’) Diffusion: Outside-in diffusion of coloring chemicals via high-temperature heat treatment to produce color and/or asterism. Example: lattice diffusion-treated sapphire
• W = Waxing/Oiling: The impregnation of a colorless wax, paraffin and/or oil in porous gemstones to improve appearance. Example: jadeite

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