sedimentary

Jasper with Quartz Veining

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Hardness: 6.5-7 on Mohs scale. Color: Greenish-grey matrix with white/tan veins. Luster: Dull to waxy. Crystal Structure: Microcrystalline (Trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.58-2.91.

Hardness: 6
Color: Greenish-grey matrix with white/tan veins
Luster: Dull to waxy

Identified March 14, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica from water-rich fluids in cracks and fissures of a host rock. This specimen appears to be a river-tumbled pebble where secondary Quartz or Chalcedony has filled fractures in a metamorphosed sedimentary or volcanic siltstone base.

Uses & applications

Used primarily for lapidary work, decorative landscaping, and as a collectible 'pocket stone'. Polished versions are common in jewelry like cabochons or beads.

Geological facts

Jasper is often referred to as the 'supreme nurturer.' This specific bi-colored appearance is common in areas with high tectonic activity where rocks are crushed and then 'healed' by silica-rich hot water.

Field identification & locations

Identify in the field by its smoothness, lack of visible crystals in the matrix (cryptocrystalline), and its ability to scratch glass. Commonly found in riverbeds, glacial tills, and beaches.

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