
sedimentary
Jasper
Silicon dioxide (SiO2)
AI-generated identification · may be incorrectHardness: 6.5-7 (Mohs); Color: Dark brown to reddish-brown with orange inclusions; Luster: Dull to waxy; Crystal structure: Microcrystalline (trigonal); Cleavage: None; Specific gravity: 2.58-2.91
- Hardness
- 6
- Color
- Dark brown to reddish-brown with orange inclusions
- Luster
- Dull to waxy
Identified More sedimentary →
Explore Jasper in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 (Mohs); Color: Dark brown to reddish-brown with orange inclusions; Luster: Dull to waxy; Crystal structure: Microcrystalline (trigonal); Cleavage: None; Specific gravity: 2.58-2.91
Formation & geological history
Formed through the accumulation of fine-grained silica, typically in volcanic ash or sedimentary environments where minerals fill cracks as part of the lithification process. Often found in riverbeds due to high resistance to erosion.
Uses & applications
Used primarily for ornamental purposes, jewelry (cabochons), lapidary art, and as a collector's specimen. Historically used for making tools and seals.
Geological facts
Jasper is an opaque variety of chalcedony. The name comes from the Old French 'jaspre', meaning 'spotted or speckled stone'. Some specimens contain iron oxide which gives them their characteristic red and brown hues.
Field identification & locations
Identify by its waxy luster when wet, high hardness (will scratch glass), and its lack of transparency even when sliced thin. This specific specimen appears water-worn, likely found in a river or creek bed.
More like this
Other sedimentary specimens
Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
fossil
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite
sedimentary
Quartz pebble
Silicon dioxide (SiO2)
sedimentary
Shale
Shale (clastic sedimentary rock)
sedimentary
Shale (or Mudstone/Siltstone)
Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
sedimentary