mineral

Quartz (Milky Quartz/Citrine Type)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to yellowish-orange; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to yellowish-orange
Luster: Vitreous (glassy) to greasy

Identified April 3, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to yellowish-orange; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through hydrothermal processes, typically as precipitation from silica-rich fluids in rock cavities or veins. These specimens often occur in granitic pegmatites or metamorphic environments.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), construction aggregates, and widely in jewelry or as metaphysical crystals.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Specimens with yellow-orange coloring are often referred to as 'citrine,' which can occur naturally or by heat-treating amethyst or smoky quartz.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and characteristic glassy luster. Look for it in quartz veins or as inclusions in igneous host rocks.

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