Jump to navigation Jump to search
Frequency common
Hardness 7
Density 2.65
Chemical Formula SiO2

Quartz is a mineral composed entirely of silicon dioxide. Both the "rock crystal" form and the "milky" form are particularly pure.

Colored varieties

Other kinds, such as rose quartz, smoky quartz, and amethyst, contain iron impurities which make them unsuitable for some applications such as glassmaking

Quartzite and Chert

Quartzite and chert, like quartz, can come in clear and white varieties, which are relatively pure silicon dioxide, and colored varieties, usually containing iron or other impurities. For some applications they can be substituted for quartz.

See Also