THE MATERIAL LIBRARY
Quartz
A silica mineral family that includes clear rock crystal and many colored varieties.
Colors & patterns
Colorless, white, smoky, pink, purple and other varieties.
Typical origins
Widely distributed; Brazil, Madagascar and the United States are among many sources.
Hardness
7 on the Mohs scale.
Choosing & setting this material
Clear or included quartz can make a striking domed cab. Ask which variety is offered and whether it is natural, synthetic or treated.
Care & cleaning
Clean gently with lukewarm water, a little mild soap and a soft cloth, then dry. Avoid steam, ultrasonic cleaners, harsh chemicals and sudden temperature changes, especially when treatments are unknown.
Origins above describe typical sources of the material, not the origin of an illustrated or stocked stone. Hardness measures scratch resistance, not resistance to breaking. Confirm the identity and treatments of the actual piece.
Further reading: Material reference · GIA: gem treatments