sedimentary

Jasper and Chert Conglomerate

Ferruginous Microcrystalline Quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale); Color: Brownish-red to cream/yellow; Luster: Dull to waxy; Structure: Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.9

Hardness: 6
Color: Brownish-red to cream/yellow
Luster: Dull to waxy

Identified April 11, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Brownish-red to cream/yellow; Luster: Dull to waxy; Structure: Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.9

Formation & geological history

Formed through the accumulation of silica-rich sediments in ancient marine or fluvial environments. The red coloring is due to iron oxide inclusions (hematite). This specimen appears to be a stream-tumbled river rock, smoothed by water erosion.

Uses & applications

Primarily used as decorative stones, lapidary materials for tumbling and polishing, and as landscaping gravel or construction aggregate.

Geological facts

Jasper has been used as a gemstone since antiquity and was mentioned in many historical texts. The red variations are often referred to as 'blood of the earth' in various folklores.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), smooth water-worn surface, and lack of visible crystals. Commonly found in riverbeds, glacial till, and coastal areas.