Quartz

Quartz Gemstone Properties
Mineral Family: Quartz Chemical Composition: SiO2, Silicon Dioxide
MOHS Hardness: 7 Specific Gravity: 2.65-2.91
Refractive Index: 1.544-1.553 Other Information: Info here
Common Enhancements: IR, Heat, Dyeing, Coating Special Care: Avoid extreme heat

Quartzis found in abundance and is most common in White.