mineral

Milky Quartz with Iron Oxides

Silicon Dioxide (SiO2) with Fe2O3 inclusions

Hardness: 7 on Mohs scale; Color: White/opaque with brown-red staining; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture).

Hardness: 7 on Mohs scale
Color: White/opaque with brown-red staining
Luster: Vitreous to waxy

Identified June 12, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White/opaque with brown-red staining; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture).

Formation & geological history

Formed in hydrothermal veins or pegmatites when silica-rich fluids cool. The brown staining is caused by secondary weathering and the infiltration of iron oxide minerals like goethite or hematite into microscopic fractures.

Uses & applications

Used as an abrasive, in glass manufacturing, as landscape stone, and by amateur rock collectors. This specific tumbled weathered piece is mostly of interest to hobbyists.

Geological facts

Quartz is the most abundant mineral in Earth's continental crust. Historically, milky quartz was often overlooked by miners in favor of metallic ores found within the same vein systems.

Field identification & locations

Identified by its ability to scratch glass (hardness) and lack of cleavage planes. Commonly found in riverbeds, glacial till, and mountainous outcroppings worldwide.

Other mineral specimens

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Biotite Schist

Biotite-rich Schist [K(Mg,Fe)3AlSi3O10(F,OH)2]

metamorphic