sedimentary
Red Jasper / Chert
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Hardness: 6.5-7 on Mohs scale; Color: reddish-orange to yellowish-brown; Luster: dull to waxy/sub-vitreous; Fracture: conchoidal to uneven; Specific Gravity: 2.58-2.91
- Hardness
- 6
- Color
- reddish-orange to yellowish-brown
- Luster
- dull to waxy/sub-vitreous
Identified More sedimentary →
Explore Red Jasper / Chert in the encyclopedia →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-orange to yellowish-brown; Luster: dull to waxy/sub-vitreous; Fracture: conchoidal to uneven; Specific Gravity: 2.58-2.91
Formation & geological history
Forms primarily through chemical precipitation in microcrystalline quartz beds or by silica replacing organic material or fine silt in low-energy aquatic environments, colored red by micro-inclusions of iron oxides like hematite.
Uses & applications
Commonly used for lapidary work, decorative cabochons, carvings, landscaping, and aggregate.
Geological facts
Red jasper is a microcrystalline variety of quartz that has been used since antiquity for seals, amulets, and ornamental jewelry. Its red coloration is due to fine hematite impurities dispersed throughout the matrix.
Field identification & locations
Can be identified in the field by its high hardness (scratches glass, cannot be scratched by a steel nail), smooth to conchoidal fracture surface, opaque red-orange-brown coloration, and dull to waxy luster. Commonly found along riverbeds, gravel bars, and sedimentary rock formations worldwide.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sedimentary Sandstone
Arenite (Sedimentary Rock)
sedimentary
Fossiliferous Concretion
Septarian Concretion containing Brachiopods/Crinoids
fossil
Shale
Shale (clastic sedimentary rock)
sedimentary
Shale
Argillaceous sedimentary rock
sedimentary
Mudstone
Argillite / Siliciclastic sedimentary rock
sedimentary