mineral

Milky Quartz with Chlorite/Iron staining

Silicon Dioxide (SiO2) with inclusions

Hardness: 7 (Mohs scale), Color: White to tan with brown/green inclusions, Luster: Vitreous/Waxy, Crystal Structure: Trigonal/Hexagonal, Cleavage: None/Conchoidal fracture

Identified June 18, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: White to tan with brown/green inclusions, Luster: Vitreous/Waxy, Crystal Structure: Trigonal/Hexagonal, Cleavage: None/Conchoidal fracture

Formation & geological history

Formed in hydrothermal veins or igneous rocks through the cooling of silica-rich fluids. The yellow-brown staining is typically iron oxide (limonite), and green areas are often chlorite inclusions.

Uses & applications

Used as a base for jewelry, tumbled stones, landscaping, and as a semi-precious collector specimen. High-purity quartz is used in electronics and glass manufacturing.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. These specific specimens are often called 'river stones' or 'beach quartz' when found water-worn.

Field identification & locations

Identified by its inability to be scratched by a steel blade (hardness 7) and its waxy luster when wet. Commonly found in riverbeds, beaches, and mountain trails worldwide.

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

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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