QUARTZ IS NOT GLASS
For our purposes, natural quartz seems hard to find pure enough to get a good resistance to cracking. All gemstones (quartz,rubies etc) used by all ball vapes are (or should be) synthetic for the high purity that is needed to get the maximum resistance to thermal shock.There are many differences between glass and quartz. The first one lies in the silicone dioxide content; glass has roughly eighty percent, while quartz can contain over ninety percent.
As an amorphous substance, glass has a random molecular structure, while quartz has a symmetrical molecular structure.
Quartz can be subject to greater temperature and pressure as compared to glass.
Both quartz and glass are utilized for electrical purposes; glass is an insulator, while quartz is a conductor.