Clear Quartz
Quartz · Semi-Precious Gemstone and Mineral Specimen
Crystal System
Trigonal; typically forms as a tumbled, smooth, and polished pebble without natural crystal faces visible.
Mineral Group
Silicates (Tectosilicate)
Chemical Formula
SiO2
Formation Process
Hydrothermal and pegmatitic crystallization from silica-rich fluids at varying temperatures and pressures within the Earth's crust.
About This Crystal
A tumbled, smooth, asymmetrical pebble with a translucent to transparent appearance and a glassy luster. It features internal fractures, subtle cloudiness, and minor localized matrix inclusions near one end.
Physical Characteristics
Colorless body color with a white streak. It has no true cleavage, exhibits conchoidal fracture, and possesses a specific gravity of approximately 2.65. It is brittle and displays piezoelectric properties under mechanical stress.
Optical Properties
Uniaxial positive with a refractive index of 1.544 to 1.553, showing double refraction and a low birefringence of 0.009.
Hardness & Durability
Origin Region
Found globally; major commercial sources include Brazil, Madagascar, the United States, and the Himalayan regions. Forms in pegmatites, hydrothermal veins, and metamorphic rocks.
Hardness & Durability
Mohs hardness of 7. It has good durability and toughness, making it suitable for general jewelry use and tumbling without major cleavage concerns.
Care & Maintenance
Safe to clean with warm soapy water and a soft brush. Avoid harsh chemicals and sudden thermal shock. Can be stored alongside other stones of similar or lesser hardness, though care should be taken to prevent scratching softer materials.
Rarity & Value
Common and widely abundant worldwide. Value is very low for tumbled specimens, usually ranging from a few cents to a few dollars depending on size and clarity.
Special Characteristics
Displays minor internal fractures and veiling, typical of natural quartz, but lacks advanced optical phenomena like chatoyancy or asterism.
Lore & History
Historically used by ancient civilizations worldwide for tools, ornaments, and scrying or divination. In modern crystal healing, it is known as the "master healer" stone, traditionally associated with the crown chakra and believed to amplify energy and intention.