Which Common Mineral Is Composed Entirely of Silicon and Oxygen?

Quartz is made up of silicon (Si) and oxygen (O). Quartz is transparent or translucent, and it's the second most abundant mineral in the Earth's crust. The many varieties of quartz are distinguished by the method of formation, impurities and the size of the grain.

The characteristics of Quartz include a glass-like appearance, a conchoidal fracture pattern and relative hardness. All varieties of quartz have essentially the same crystalline structure and chemical composition.

One type of quartz is rose quartz, which has a rose or pink color. Citrine, amethyst, smoky quartz and milky quartz are other common types of quartz.