mineral

Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Translucent white to opaque milky white with yellow-brown iron oxide staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal (hexagonal system); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on the Mohs scale
Luster: Vitreous to greasy

Identified March 4, 2026More mineral →

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Physical properties

Formation & geological history

Formed via hydrothermal activity where silica-rich fluids cool and crystallize in veins or volcanic cavities. It can be found in a wide variety of geological ages and environments, particularly in igneous and metamorphic terrains.

Uses & applications

Used as an abrasive in industry, in the production of glass and silicon chips, as a construction aggregate, and frequently in lapidary work for cabochons or decorative carvings.

Geological facts

The milky appearance is caused by tiny inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and characteristic waxy/greasy luster on fresh surfaces. Often found in riverbeds or near mountain ranges.

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