Hyaline quartz or rock crystal has been known and appreciated since prehistoric times, because it is easily available and suitable for use as a tool thanks to its hardness. The oldest name, reported in Greek by Theophrastus in the fourth century. to. C, is “krýstallos”, which means ice. For Pliny, a Latin author of the first century. d. C, the “crystallus” is “ice frozen beyond all limits”. Quartz is one of the most widespread minerals in the earth's crust and is a significant component of many types of igneous, metamorphic and sedimentary rocks. When pure, quartz forms colorless, transparent and very hard crystals, with a luster similar to that of glass. This natural form of silicon dioxide is found in an impressive range of varieties and colors. It is widely used in industry and as an ornamental stone.
Dimensions
Height (cm): about 2.5
Depth (cm): about 2
Width (cm): 2 approx
Weight (g): 13 approx
Property
Chemical Formula: SiO2
Mohs scale: 7
Relative density: 2.65
Crystalline System: Trigonal
