sedimentary
Jasper
Silicon dioxide (SiO2) with iron impurities
Hardness: 6.5-7 on Mohs scale; Color: Reddish-brown/Maroon; Luster: Dull to waxy; Crystal Structure: Microcrystalline; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.58-2.91
- Hardness
- 6
- Color
- Reddish-brown/Maroon
- Luster
- Dull to waxy
Identified More sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 on Mohs scale; Color: Reddish-brown/Maroon; Luster: Dull to waxy; Crystal Structure: Microcrystalline; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.58-2.91
Formation & geological history
Formed through the deposition of silica from water-rich environments, often in volcanic or hydrothermal settings where iron oxides provide the deep red/brown coloration. Can be found in various geological ages ranging from Precambrian to recent.
Uses & applications
Commonly used as a gemstone in necklaces and bracelets, for decorative carvings, and as a popular specimen for rock tumbling and collection.
Geological facts
Jasper is an opaque variety of chalcedony. The name comes from the Greek word 'iaspis', meaning 'spotted stone'. It was one of the stones in the High Priest's Breastplate mentioned in the Bible.
Field identification & locations
Identify by its opacity (even on thin edges), its hardness (will scratch glass), and its smooth, water-worn texture if found on beaches or in riverbeds. Common in Western US, Brazil, and India.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Sandstone Grain
Clastic Sedimentary Rock Grain (SiO2 dominated)
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Sandstone
Arenite
sedimentary