Now that we have discussed what gemstones are, I’d like to explore the treatments which can be done to gemstones. According to Fire Mountain Gems and Beads, gemstone treatments can be defined as follows:
Assembled: Products made of multiple layers or combinations of manufactured and/or natural materials joined together.
Bleaching: The use of chemical agents to lighten or remove a gemstone’s color
Coating: Surface enhancements to improve appearance, provide color or other special effects.
Dyeing: The introduction of coloring matter into a gemstone to give it new color, intensify present color or improve color uniformity.
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.
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.
Heating: The use of heat to effect desired alteration of color, clarity and/or phenomena.
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.
Manmade: Fabricated products.
Natural: Stones which are not currently known to be enhanced.
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.
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.
Stabilization (Bonding): The use of a colorless bonding agent (commonly plastic) with a porous gemstone to give it durability and improve appearance.
Synthetic: These are manmade materials which have essentially the same optical, physical and chemical properties as a naturally occurring counterpart.
Diffusion: The use of chemicals in conjunction with high temperatures to produce color and/or asterism (star-like) inclusions.
Waxing/Oiling: The impregnation of a colorless wax, paraffin and/or oil in porous opaque gemstones to improve their appearance.
If you go to the link above, you will see that there are some treatments I have not listed. The list I have here shows the enhancements that are likely to be used on the gemstones I use in my jewelry. As much as possible, I try to use natural gemstones without any treatments. The most common exception to this is when I use freshwater pearls because they are almost always treated by bleaching to give them the nice white color most people desire in pearls. Turquoise is also always treated by stabilization because it is not strong enough in its natural state to stand up to the wear of being used in jewelry.
Now, I know what your next question is. “How do these treatments affect the value of the gemstones?” If you compare a completely natural stone to a stone identical to it with the exception that it has been dyed or heated to enhance the color, the untreated stone will be more valuable than the treated stone. Keep in mind, there are several stones which are always treated in some way because they would not be strong enough for use in jewelry in their natural state.
I hope this cleared up some questions you might have had, and if you didn’t have questions, I hope it leaves you feeling a bit more knowledgeable about what you are getting in your gemstone jewelry. I know I have a better understanding of these terms and I’ve been seeing them for several years now.
Thanks for reading!