Turquoise is a beautiful opaque blue-green gemstone that has been popular in jewelry and carvings for thousands of years. It is often imitated, and lower-grade turquoise is also often enhanced to be usable in jewelry.
When you're buying turquoise, it's best to be aware of some terms to know exactly what you are purchasing. Two common turquoise imitations are dyed howlite and dyed magnesite.
Stabilized turquoise is a low-grade turquoise that has had a material, usually epoxy, bonded to it to give it enough strength to be used in jewelry. Turquoise is also sometimes dyed to give it a better color. Reconstituted turquoise is made up of powdered turquoise mixed with resin and dyes to create the finished product.
Untreated turquoise with a good color that has never been dyed is the most valuable, but the other forms are also beautiful and work well in jewelry designs.