mineral

Quartz (Milky/Yellowish)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to yellowish due to iron staining; Luster: Vitreous (glassy) to waxy; Crystal structure: Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to yellowish due to iron staining
Luster: Vitreous (glassy) to waxy

Identified April 7, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It can occur in various geological environments from igneous plutons to metamorphic basement rocks. This specimen is a water-worn river pebble.

Uses & applications

Industrial use in glassmaking, abrasives, and electronics (as oscillators). Also popular among collectors and used for decorative tumbled stones and metaphysical purposes.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'quarz', which is of Slavic origin. It exhibits piezoelectric properties, creating an electric charge when mechanical stress is applied.

Field identification & locations

Identify by its hardness (it can scratch glass and steel) and lack of cleavage. Look for the characteristic conchoidal fracture if broken. Commonly found in riverbeds, beaches, and mountainous regions worldwide.