sedimentary/metamorphic

Jasper and Quartzite Pebble

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Hardness: 6.5-7 (Mohs scale); Colors: Red (iron oxide), tan/gray/white (quartzite); Luster: Waxy to vitreous; Texture: Smooth, water-worn, cryptocrystalline structure; Specific Gravity: 2.6-2.9.

Hardness: 6
Luster: Waxy to vitreous

Identified March 18, 2026More sedimentary/metamorphic →

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Physical properties

Hardness: 6.5-7 (Mohs scale); Colors: Red (iron oxide), tan/gray/white (quartzite); Luster: Waxy to vitreous; Texture: Smooth, water-worn, cryptocrystalline structure; Specific Gravity: 2.6-2.9.

Formation & geological history

Formed through the silicification of fine-grained sedimentary or volcanic ash deposits, later undergo secondary mineralization. This specific specimen is a 'river rock' or 'beach pebble,' indicating it was shaped by fluvial or marine erosion over thousands to millions of years.

Uses & applications

Commonly used for lapidary work (tumbling/polishing), garden landscaping, aquarium decor, and as a semi-precious gemstone for decorative jewelry.

Geological facts

Jasper is often referred to as the 'Supreme Nurturer.' The red coloration in the band is caused by inclusions of Hematite (iron oxide). The smooth, rounded shape is a result of hydraulic action, where constant water movement causes rocks to knock against each other, grinding away sharp edges.

Field identification & locations

Identify in the field by its hardness (cannot be scratched by a steel knife) and smooth, rounded water-worn texture. Commonly found in riverbeds, glacial moraines, and along coastlines globally. Collectors look for unique banding or 'picture' patterns within the stone.

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