mineral

Quartz Pebble (with Iron Inclusions)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to tan with patches of yellowish-brown; Luster: Vitreous to waxy; Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to tan with patches of yellowish-brown
Luster: Vitreous to waxy

Identified March 29, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal fluids or within igneous pegmatites. This specific specimen has been further shaped by fluvial (water) erosion into a rounded 'river stone' pebble. Its age can range from millions to over a billion years depending on the source rock.

Uses & applications

Used primarily in landscaping, construction aggregate, and as a raw material for glass making and electronics. Rounded pebbles are also popular for meditation stones and aquarium decor.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The yellowish-brown staining on this specimen is likely limonite or goethite, which are iron oxide minerals that weathered into the quartz's micro-fractures.

Field identification & locations

Identify in the field by its hardness (it should easily scratch glass) and its smooth, water-worn exterior. It is commonly found in riverbeds, glacial tills, and beaches worldwide. This specimen shows typical 'Iron Staining.'

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