igneous

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) in Rhyolitic Matrix

Hardness: 7 (Quartz); Color: White to milky white vein in brownish-grey matrix; Luster: Vitreous to waxy; Structure: Hexagonal (microcrystalline in this form); Cleavage: None (conchoidal fracture).

Hardness: 7 (Quartz)
Color: White to milky white vein in brownish-grey matrix
Luster: Vitreous to waxy

Identified February 21, 2026More igneous →

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Physical properties

Hardness: 7 (Quartz); Color: White to milky white vein in brownish-grey matrix; Luster: Vitreous to waxy; Structure: Hexagonal (microcrystalline in this form); Cleavage: None (conchoidal fracture).

Formation & geological history

Formed through hydrothermal processes where silica-rich hot fluids circulate through fractures in igneous rocks, cooling to deposit quartz. Frequently associated with volcanic activity in the Tertiary period.

Uses & applications

Quartz is used in glassmaking, electronics (piezoelectric properties), and construction. This specific rough specimen is primarily of interest to hobbyist collectors or as a decorative garden stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Vein quartz like this often serves as an indicator for prospectors searching for gold, as gold is frequently found within quartz veins.

Field identification & locations

Identify by its ability to scratch glass and its lack of reaction to acid. Commonly found in mountainous regions or areas with historical volcanic activity. Best collected from road cuts or stream beds.

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