There are several widely used treatments being utilized in the gemstone bead market. Here is a list of the standard treatments as described by the American Gem Trade Association. The FTC requires that this information be disclosed when any gemstones are sold.

I’ve added my own notes to each treatment, and some stones that commonly use the treatment.

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

There are a lot of assembled stones out there. You’ll also hear them referred to as being “block material” This means the stone has been powdered then mixed into resin, formed into a block, then cut into shape. Turquoise, Malachite, Lapis, and Coral are commonly used. In bead form, it’s often super cheap, and oddly uniform.

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

Coral, pearls, wood, and bone are commonly bleached to produce an even, white color.

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

Shell and Turquoise are often coated to protect or enhance color.

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

Most common treatment out there. Brightly colored Agates are most likely dyed, as well as Turquoise, Coral, and Rose Quartz, Iolite, Amethyst, and Citrine.

(E) - Enhanced: This indicates that this type of gemstone is routinely enhanced.

Used when the exact method of enhancement is not known

(F) - Filling: As a by-product of heat enhancement, 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.

Smoky Quartz and Citrine are often heated to produce deep, uniform color. Citrine is often heated Amethyst.

(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: Man-made 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.

Cherry Quartz, Blueberry Quartz, Pineapple Quartz, or any other fruity quartz are all man made. They’re GLASS that has been infused with color.

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

(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 man-made material into fissured transparent/translucent gemstones to improve appearance.

Emerald

(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.

Smoky Quartz is most often irradiated or heated. Irradiated stones are NOT radioactive.

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

Turquoise. Notice a pattern here?

(Syn) - Synthetic: These are man-made 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.

There are a few other methods used in the bead world that aren’t in the above list. I’ve come across these at trade shows all over the country. One of the most common, and easiest to detect is powder polishing. Translucent and transparent stones are often given a polish with a colored powder that fills in any little cracks or imperfections, and makes the color richer or more even. The easiest way to check for this is to rub the string the beads are sold on. The powder reside will rub off onto your skin. It is easily washed off, but beware, those nice dark Garnets may be pale pink or ruddy brown when you get them home! Iolite, garnet, amethyst, citrine, peridot, and rose quartz commonly receive this finishing polish. This is a good reason to wash your strands before you use them. Warm soapy water will do the trick.

• Tip – When shopping at trade shows, I take a special buying kit along with me. Included in that kit is a small spray bottle with soapy water in it and a white cotton hand towel. Most vendors are more than happy to allow me to check a strand before I buy it with a quick spray and wipe. If a vendor won’t let me, I won’t buy from them! Also included in my kit, an electronic gram scale. Higher end stones are often priced by the gram. A current trend is to put decorative tassels on the strands for display. The selling weight often includes these tassels. Ask a vendor to weigh the strand on your scale without the tassels, then calculate the price. The sellers I trust, do this for me!

It is your responsibility as a buyer to educate yourself. It is the vendors responsibility, and Federal Law that all treatments be disclosed at each level of sale. Ask questions and build relationships with your suppliers, you’ll be glad you did!

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