sedimentary
Jasper (likely brecciated jasper)
Microcrystalline quartz, SiO₂; iron-oxide-stained chalcedony
AI-generated identification · may be incorrectOpaque, mottled reddish-brown and gray, with a waxy to dull luster and no visible cleavage; Mohs hardness about 6.5–7. The small, irregular piece appears naturally fractured or tumbled.
Identified More sedimentary →
Explore Jasper (likely brecciated jasper) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Opaque, mottled reddish-brown and gray, with a waxy to dull luster and no visible cleavage; Mohs hardness about 6.5–7. The small, irregular piece appears naturally fractured or tumbled.
Formation & geological history
Silica-rich fluids filled cavities and fractures, then iron oxides colored the chalcedony; jasper deposits form in many geological settings and span a wide range of ages.
Uses & applications
Used for beads, cabochons, ornamental objects, and lapidary collecting; this small rough piece has little industrial value.
Geological facts
Jasper is a variety of chalcedony, itself microcrystalline quartz; brecciated varieties contain angular fragments cemented by silica.
Field identification & locations
Look for opacity, hardness sufficient to scratch glass, and a fine-grained quartz texture; common worldwide in silica-rich volcanic and sedimentary terrains. The photo alone cannot confirm the exact variety.
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