Glossary
Quartz
Quartz refers to a crystalline and very hard mineral composed on silica that is found worldwide in many different types of rocks that includes sandstone and granite. Quartz comes in m any forms, including amethyst, aventurine, citrin, opal, rock crystal, tiger's eye, rose quartz,and many others. Rutilated quartz and tourmalinated quartz have needle-like inclusions of other minerals.