mineral

Quartz (Granular Milky Quartz fragment)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: semi-opaque white to translucent gray; Luster: vitreous (glassy) to waxy; Crystal structure: Hexagonal (trigonal); Cleavage: none (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: semi-opaque white to translucent gray
Luster: vitreous (glassy) to waxy

Identified March 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. This fragment shows a granular texture typical of pegmatites or metamorphic quartzite fracturing. It is likely from the Phanerozoic eon, though quartz is found in rocks of all geological ages.

Uses & applications

Industrial uses include glass making, abrasives, and electronics (due to piezoelectric properties). In jewelry, it is used for beads and cabochons. Large quantities are used in construction as aggregate.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, it was used by many ancient cultures for stone tools and ritual objects. It is the only mineral on the Mohs scale that is ubiquitous in almost every environment.

Field identification & locations

Identify in the field by its hardness (it will easily scratch glass and steel) and lack of cleavage. It is found globally in riverbeds, mountains, and beaches. Small loose fragments like this are often found in driveway gravel or weathered out of granite outcrops.

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