mineral

Milky Quartz Pebble with Iron Inclusions

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Creamy white with yellow-brown iron oxide stains; Luster: Vitreous to greasy; Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Creamy white with yellow-brown iron oxide stains
Luster: Vitreous to greasy

Identified June 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed primarily in hydrothermal veins and pegmatites. The rounded shape suggests it was eroded and transported by water (alluvial) in a river or stream environment over thousands of years.

Uses & applications

Used in construction as a component of gravel, as a decorative landscape stone, and as a source for silicon in electronics. Common specimens like this are primarily of interest to beginner collectors.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. The yellow staining in this sample is likely Limonite or Goethite, common oxidation products of iron-bearing minerals.

Field identification & locations

Identified by its hardness (it can scratch glass), the lack of cleavage, and its waxy or vitreous luster. These are often found in riverbeds, glacial tills, and along coastlines.

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

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Epidote

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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