from The Bead Scoop Vol. II, Issue 1 Mar 2008
Q. What does “stabilized turquoise” mean?
A. As we all know, turquoise is a beautiful gemstone that has been prized for centuries in all corners of the world. One of the oldest pieces of jewelry was a turquoise bracelet found on a 7000-year-old mummified Egyptian queen, and its popularity hasn’t waned even to this day. With every fashionable gemstone come the gemstone imitations, and it is often hard to discern what is natural, enhanced, or imitated – especially with today’s advanced lapidary and mining technologies. There are four categories for turquoise as described by law (not including flat-out imitations such as dyed stones or plastics).
Natural turquoise: Turquoise has a hardness of 5-6 (10 is the hardest) and it is very porous, sometimes even chalky. Natural turquoise tends to be harder, exhibiting bright natural color. It is not treated in any way except cutting and polishing. Less than 3% of turquoise on the market is natural.
Stabilized turquoise: Softer, chalkier turquoise can be too fragile for practical uses and things like light, heat, perspiration and chemicals can cause negative color changes in all forms of the stone. When soft turquoise is soaked in artificial resin it permanently hardens the stone and deepens the color. The color and hardness are thus “stabilized”. Most turquoise on the market is stabilized and is less expensive than the natural stone.
Treated turquoise: This is stabilized turquoise that has dye included in the resin. The colors will look more artificial, bright, consistent, etc. and the prices are lower than stabilized turquoise. Also called “dyed turquoise”.
Reconstituted turquoise: Soft turquoise that has been ground to a powder, combined with acrylic or epoxy resin, dyed and formed into a block for cutting. This has a look and feel of acrylic and is the least expensive form.
The more you know about the and its various forms, the less you will fall prey to imitations. Most of the time, turquoise will be labeled accurately and the price will reflect the material. If you like a stone and come to find that it is dyed or treated, ask yourself if that really matters. For some people purity of the stone is paramount; for others, the attractiveness of a stone (especially one that works into a great beadwork design!) is what counts. An educated choice is the best option either way!