mineral

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to yellowish-tan; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white to yellowish-tan
Luster: Vitreous to greasy

Identified May 18, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to yellowish-tan; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through hydrothermal processes or igneous intrusion. This specimen likely originated from a quartz vein and acquired its yellow/orange tint from iron oxide (limonite) weathering in the surrounding soil or water.

Uses & applications

Used in the production of glass, ceramics, and electronics (due to piezoelectric properties). Often collected as decorative specimens or used as landscaping material.

Geological facts

Quartz is one of the most abundant minerals in Earth's crust. 'Milky' quartz gets its white appearance from microscopic fluid inclusions trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (it will scratch glass and steel) and lack of cleavage. Common worldwide, especially in mountain ranges and gravel deposits.

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