mineral

Milky Quartz (or Iron-Stained Quartz)

Quartz (Silicon Dioxide, SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Milky white with yellowish-brown iron oxidation staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white with yellowish-brown iron oxidation staining
Luster: Vitreous to greasy

Identified April 10, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes where silica-rich fluids cool in veins, or as a primary mineral in igneous and metamorphic rocks. This specimen likely formed in a hydrothermal vein and has been weathered at the surface, leading to the iron-oxide staining (rust colors).

Uses & applications

Used in glass manufacturing, as an abrasive, in electronics (piezoelectric properties), in construction as aggregate, and as a semi-precious gemstone or metaphysical specimen.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. Milky quartz gets its opaque white color from microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (it will scratch glass and steel), lack of cleavage, and waxy/vitreous luster. Common in mountainous regions, riverbeds, and as veins in surrounding rock. Tips for collectors: check for crystal faces in cavities (vugs).