mineral

River Quartz (Milky and Smoky mix)

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale. Color: Translucent white (milky) to yellowish-brown (smoky due to natural radiation or impurities). Luster: Vitreous to waxy. Crystal Structure: Hexagonal/Trigonal. Cleavage: Indistinct/Conchoidal fracture.

Hardness: 7 on the Mohs scale
Luster: Vitreous to waxy

Identified March 28, 2026More mineral →

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Physical properties

Formation & geological history

Formed from hydrothermal veins or cooling igneous magma. This specific specimen has been Rounded and smoothed through fluvial (river) erosion over thousands of years.

Uses & applications

Commonly used for lapidary work (tumbled stones), decorative landscaping, and as a component in glass making or construction aggregate. It is a staple for rock-collecting beginners.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. This specimen shows 'water-worn' features, meaning it traveled long distances in a stream bed to achieve its rounded, pebble-like shape.

Field identification & locations

Identify by its hardness (it will scratch glass) and lack of visible grains. Commonly found in riverbeds, beaches, and gravel pits globally. Collectors look for clarity or unique inclusions.

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