mineral

Quartz (Smoky/Milky variety with matrix)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Translucent grey to white with brownish iron staining; Luster: Vitreous (glassy) to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Translucent grey to white with brownish iron staining
Luster: Vitreous (glassy) to greasy

Identified February 21, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal activity or cooling of silica-rich magma/lava. This specimen likely originated in a pegmatite vein or as a component of granite, potentially dating back hundreds of millions of years depending on the local geology.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), construction as an aggregate, and widely collected as mineral specimens or used in jewelry as semi-precious stones.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'Quarz', which had its origins in Slavic and West Slavic languages. Ancient Greeks referred to it as 'krustallos' meaning ice.

Field identification & locations

Identify in the field by its hardness (it will scratch glass and steel), lack of cleavage, and glassy fracture. It is ubiquitous worldwide. For collectors, look for hexagonal crystal faces and transparency.

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