mineral

Milky quartz (iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Likely massive, translucent-to-white quartz with rusty-brown iron-oxide staining. Mohs hardness 7; vitreous luster, hexagonal crystal system, no cleavage, and uneven to conchoidal fracture; specific gravity about 2.65.

Identified October 11, 2026More mineral →

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Physical properties

Formation & geological history

Quartz commonly crystallizes from silica-rich fluids in veins and pegmatites, or grows in cavities in igneous and metamorphic rocks. Its age cannot be determined from the photograph and depends on its geological setting.

Uses & applications

Commonly collected; quartz is also used in glassmaking, abrasives, electronics, and decorative stone. This small rough piece has limited jewelry value unless cut or polished.

Geological facts

Quartz is one of Earth’s most abundant minerals. Brown patches may be iron oxides coating or staining the quartz.

Field identification & locations

Look for glassy luster, hardness sufficient to scratch ordinary glass, and lack of cleavage; avoid identifying by color alone. Quartz occurs worldwide, especially in veins and pegmatites.