Quartz
Quartz is derived from the German word ‘quarz’, which incidentally has Slavic origins. Czech miners called quartz ‘k?emen’. After feldspar, quartz is one of the most abundant minerals found in the continental crust of the Earth. Quartz comes in a number of varieties – with most of them being semi-precious gemstones.
In the Middle East and Europe, quartz has been used quite commonly, even in ancient times for jewelry making and hard stone carvings. One of the many theories regarding quartz comes from Pliny the Elder, a Roman naturalist who believed quite firmly that quartz was water ice which had been frozen permanently.
Varieties of quartz according to color
Pure quartz is also called rock crystal and clear quartz is translucent.
Citrine is the type of colored quartz in which its color ranges from pale yellow to brown. It is almost impossible to differentiate a cut citrine from yellow topaz. Finding citrines naturally is quite rare. Commercial citrines are most often amethysts which have been artificially heated or smoky quartz. The leading producer of citrine is Brazil.
Rose quartz ranges from a pale pink to a rosy red shade. The color of a rose quartz is determined by the amount of traces of titanium, iron or manganese found in the stone itself. X-ray diffraction studies indicate that the color of a rose quartz comes from very thin microscopic fibers of dumortierite contained in the quartz.
Amethyst is the most popular variant of the quartz family. Its color ranges from a bright purple to dark or dull shade.
Smoky quartz is an almost translucent, but gray stone. Its clarity ranges from fully transparent to an opaque. Some smoky quartzes are black.
Milky quartz is the most common of the quartzes and is milky white in color.