sedimentary
Jasper (Green Jasper/River Stone)
Silicon Dioxide (SiO2) with impurities
Hardness: 6.5-7 (Mohs scale), Color: Dull green with ochre/red spots and white quartz veins, Luster: Waxy to vitreous when wet, Structure: Microcrystalline, Cleavage: None (conchoidal fracture).
- Hardness
- 6
Identified More sedimentary →
Explore Jasper (Green Jasper/River Stone) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 (Mohs scale), Color: Dull green with ochre/red spots and white quartz veins, Luster: Waxy to vitreous when wet, Structure: Microcrystalline, Cleavage: None (conchoidal fracture).
Formation & geological history
Formed through the infiltration of silica-rich fluids into sediment or volcanic ash, often containing iron oxides or chlorite that provide the green hue. This water-worn specimen likely originated from Mesozoic or Cenozoic deposits.
Uses & applications
Used primarily as decorative lapidary material, for tumbling, jewelry (cabochons), and as landscaping stone.
Geological facts
Jasper is an opaque variety of chalcedony. The name comes from the Greek word 'iaspis', meaning 'spotted stone'. Green jasper was historically highly valued in the ancient world for its supposed healing properties.
Field identification & locations
Identify in the field by its smooth, water-worn exterior, waxy texture, and extreme hardness (it will scratch glass). Commonly found in riverbeds, gravel bars, and coastal areas where harder metamorphic or sedimentary rocks are weathered out.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Cone-in-cone structure (Limestone)
Cone-in-cone structure (Secondary Sedimentary Structure)
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Sandstone Grain
Clastic Sedimentary Rock Grain (SiO2 dominated)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary