My+minerals+-+Quartz


 * Quartz** is the second most abundant mineral in the Earth's continental crust, after feldspar.

It has a hardness of 7 on the Moh's hardness scale.

The word "quartz" is derived from the German word "quarz", which was imported from Middle High German, "twarc", which originated in Slavic.

Most pieces of beach sand are small pieces of quartz.

Pure quartz, traditionally called **rock crystal** (sometimes called **clear quartz**), is colorless, but it comes in lots of other colours. Common colored varieties include citrine, rose quartz, amethyst, smoky quartz, milky quartz, and others.