sedimentary
Red Jasper (Chert)
Silicon Dioxide (SiO2) with iron oxide inclusions
Hardness: 6.5-7 (Mohs scale), Color: Red, brown, and yellowish-tan, Luster: Dull to waxy, Crystal structure: Microcrystalline/Cryptocrystalline, Cleavage: None (conchoidal fracture)
- Hardness
- 6
Identified More sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 (Mohs scale), Color: Red, brown, and yellowish-tan, Luster: Dull to waxy, Crystal structure: Microcrystalline/Cryptocrystalline, Cleavage: None (conchoidal fracture)
Formation & geological history
Formed from the deposition of silica-rich fluids in cracks or as nodules within sedimentary or volcanic rocks. The red color is caused by the oxidation of iron (hematite) during formation.
Uses & applications
Commonly used for lapidary work, jewelry (cabochons), interior decoration, and as a healing stone in metaphysical practices.
Geological facts
The name jasper is derived from the Greek 'iaspis', meaning spotted stone. It has been used since antiquity for royal seals and amulets.
Field identification & locations
Identify by its opacity (even on thin edges), smooth conchoidal fracture, and inability to be scratched by a steel knife. Frequently found in riverbeds and coastal regions as water-worn pebbles.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite (primarily SiO2)
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
sedimentary