mineral

Quartz (Iron-Stained Quartz Pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Milky white to translucent with yellowish-brown iron oxidation staining; Luster: Vitreous (glassy) to waxy; Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Luster: Vitreous (glassy) to waxy

Identified February 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes or igneous crystallization; this specific rounded specimen show signs of alluvial/river erosion where it was tumbled in water over long geological periods. Common in varying ages from Precambrian to recent deposits.

Uses & applications

Industrial use as an abrasive, glass manufacturing, and electronics (piezoelectric properties). Large specimens are used for landscaping, while small rounded ones are often sold for home decor or as 'pocket stones' for crystal healing enthusiasts.

Geological facts

Quartz is one of the most abundant minerals in Earth's continental crust. The yellow-brown spots are typically limonite or goethite (iron oxide) that has seeped into micro-fractures in the stone.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (which is softer than 7) and its lack of cleavage. Found globally in riverbeds, glacial tills, and mountainous regions. Collectors look for clarity or unique inclusions.

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