The colorless and transparent variety of quartz is known as rock crystal, which is the most widely distributed variety of quartz. Rock crystal got is name from the Greek word for “ice” as it is said that, the rock crystal was eternally frozen. Rock crystals, which weigh many tons, have been found but the clear or flawless material is rare. Rock crystal becomes smoky quartz when it is treated with x-ray and radium.

Locations:

The most important source of rock crystal is Brazil. Fine crystals come from Swiss and French Alps, Madagascar, USA and the former USSR.

Chemical Composition: Silicon Dioxide
Crystal Structure: Trigonal
Hardness: 7
Specific Gravity: 2.65
Refractive Index: 1.54-1.55
Colors: Colorless.
Luster: Vitreous

Astrological Relevance:

Rock Crystal is considered as one of the birthstones for the zodiac sign of Pisces (February 21 To March 21).