Quartz Crystal

Quartz as a mineral:

Quartz is a mineral composed of silicon dioxide (SiO2) and can form crystals in various environments, including within magma cooling to form igneous rocks or precipitating from water to create sedimentary rocks.

Quartz as a metamorphic rock:

When a sedimentary rock like sandstone, which is primarily composed of quartz grains, undergoes high pressure and temperature during metamorphism, it transforms into a metamorphic rock called quartzite.

There are also sedimentary forms of quartz. These, however, classify as chemical sedimentary rocks. They are formed through the chemical processes of a mineral substance precipitating out of a solution or as a deposit left after evaporation.

Colors It Comes In - Clear (no impurities), light pink (titanium, iron, or manganese), milky white (tiny bubbles of gas or liquid), purple (iron), yellow (iron), or brown (extra silicon)

Fracture Pattern - Conchoidal

Shape - Typically six-sided prisms with steep pyramidal terminations. They can be stubby ("short prismatic") or elongated and even needle-like.

Luster - Crystals are vitreous (glass-like), massive form is dull or waxy.

Where It Can Be Found - It is found in all forms of rock: igneous, metamorphic and sedimentary. Quartz is physically and chemically resistant to weathering. When quartz-bearing rocks become weathered and eroded, the grains of resistant quartz are concentrated in the soil, in rivers, and on beaches.

Hardness On The Mohs Scale - 7 Out Of 10