mineral

Milky quartz crystal cluster

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; white to translucent, with vitreous luster and irregular interlocking crystals. Quartz is trigonal, lacks cleavage, and has conchoidal fracture; specific gravity is about 2.65.

Identified September 15, 2026More mineral →

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Physical properties

Hardness 7 Mohs; white to translucent, with vitreous luster and irregular interlocking crystals. Quartz is trigonal, lacks cleavage, and has conchoidal fracture; specific gravity is about 2.65.

Formation & geological history

Likely formed as hydrothermal quartz in a mineral vein or cavity, where silica-rich fluids cooled and crystallized. Exact geological age and locality cannot be determined from the photograph.

Uses & applications

Common quartz is used in glass, ceramics, abrasives, engineered stone, and electronics; attractive clusters are sold as inexpensive display specimens.

Geological facts

The white appearance results mainly from microscopic fluid inclusions, fractures, and light scattering. Individual quartz crystals typically form six-sided prisms capped by pyramidal faces, though this specimen is heavily intergrown.

Field identification & locations

Identify by its glassy sparkle, lack of obvious cleavage, hardness sufficient to scratch ordinary glass, and resistance to dilute acids. Similar-looking calcite is softer (Mohs 3) and commonly reacts with acid.