Quartz
Quartz is a mineral that belongs to the silicon oxides. It has a crystalline structure and forms crystals in the shape of a hexagonal column, which is called a prism. Its crystals can be transparent to translucent. The colour of quartz usually ranges from colourless to white, grey to various shades of brown. However, there are also rare varieties of quartz with pink, green, blue or even black colour.
In nature, quartz occurs in different types of rocks such as veins, pegmatites, sedimentary rocks or metamorphosed rocks. It is most commonly found in the form of crystals, but also in the form of amorphous quartz, which does not have a crystalline structure.
Quartz forms a number of varieties, including star quartz, clear crystal, rose quartz, brown or smoky quartz, chalcedony, banded agate, onyx, purple amethyst, tiger's eye, ironstone, jasper, yellow citrine, and black morion.
