mineral

Quartz (Milky Quartz with Iron Staining)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white with orange/brown iron oxide staining; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white with orange/brown iron oxide staining
Luster: Vitreous (glassy) to greasy

Identified February 19, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. This specific specimen is likely a water-worn river stone or glacial cobble, rounded by erosion over thousands of years.

Uses & applications

Used in glassmaking, ceramics, and as an abrasive. In jewelry, it is used for cabochons or beads. Industrially, it is vital for manufacturing silicon wafers for electronics.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The 'milky' appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identified by its ability to scratch glass, its lack of cleavage, and its waxy/glassy appearance. It is found globally in riverbeds, mountains, and deserts. Collectors find them easily in areas with metamorphic or igneous activity.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

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

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral

Epidote

Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

mineral