Quartz
Silicon Dioxide (Quartz var. Milky Quartz / Crystalline Quartz) · Mineral Specimen and Semi-Precious Stone
Crystal System
Trigonal crystal system, forming massive or crystalline aggregates with a druzy-like surface texture in this specimen.
Mineral Group
Silicates (specifically Tectosilicates)
Chemical Formula
SiO2
Formation Process
Hydrothermal and magmatic processes, precipitating from silica-rich aqueous solutions at varying temperatures and pressures within crustal rocks.
About This Crystal
The specimen features a dense cluster of small, interlocking crystalline structures with a shimmering, translucent-to-opaque white and grayish appearance. It exhibits a vitreous to pearly luster across fractured or reflective faces, showcasing characteristic conchoidal fracture surfaces and micro-crystalline growth patterns.
Physical Characteristics
Color is predominantly white to translucent gray with a white streak. It has no true cleavage, breaking with a distinct conchoidal fracture. Specific gravity is approximately 2.65, and it is brittle with strong piezoelectric and pyroelectric properties.
Optical Properties
Singly refractive to uniaxial positive with a refractive index of approximately 1.544 to 1.553. Birefringence is weak at 0.009. Displays no significant pleochroism due to lack of coloration.
Hardness & Durability
Origin Region
Found globally; major deposits in Brazil, Madagascar, the United States, and the Alps. Typically forms in hydrothermal veins, pegmatites, and sedimentary environments.
Hardness & Durability
Mohs hardness of 7, making it durable and resistant to scratching. It has good toughness and stability against most common chemicals, though it can be damaged by hydrofluoric acid.
Care & Maintenance
Can be safely cleaned with warm soapy water and a soft brush. Avoid harsh chemical cleaners and extended exposure to high heat. Safe for ultrasonic cleaners unless heavily fractured.
Rarity & Value
Extremely common mineral worldwide. Value is generally low for common quartz specimens, though fine aesthetic mineral specimens, large crystals, or rare color varieties can command higher prices among collectors.
Special Characteristics
Exhibits strong piezoelectric properties (generating electric charge under mechanical stress) and triboluminescence when crushed or rubbed in the dark.
Lore & History
Quartz has been utilized by human civilizations for millennia for tools, ornaments, and ritual objects. In metaphysical traditions, clear and white quartz is considered a master healer stone associated with all chakras, traditionally believed to amplify energy, enhance clarity, and promote spiritual growth.