Quartz – lots of looks, one cool mineral

Quartz is the most common mineral found in the Earth’s crust.  Fairly hard, quartz is a 7 on the Mohs hardness scale which has a range from 1 (softest) to 10 (hardest).  Quartz, which is sometimes called “Rock Crystal,” is often colorless and has a glassy (shiny) appearance.  Quartz has a white streak when rubbed […]