sedimentary
Jasper
Microcrystalline Quartz (SiO2)
Hardness of 6.5 to 7 on the Mohs scale, reddish-brown color due to iron inclusions, waxy to dull luster, cryptocrystalline or microcrystalline structure, conchoidal fracture with no true cleavage, and a specific gravity around 2.65.
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 of 6.5 to 7 on the Mohs scale, reddish-brown color due to iron inclusions, waxy to dull luster, cryptocrystalline or microcrystalline structure, conchoidal fracture with no true cleavage, and a specific gravity around 2.65.
Formation & geological history
Formed through the silification of sedimentary or volcanic rocks, where silica-rich fluids precipitate microcrystalline quartz in pore spaces or fractures, often in ancient marine or hydrothermal environments.
Uses & applications
Used primarily in lapidary arts, ornamental carvings, polished cabochons for jewelry, and as a decorative stone.
Geological facts
Jasper has been used since ancient times to create seals, talismans, and decorative items. Red jasper specifically gets its vibrant color from hematite or iron oxide impurities.
Field identification & locations
Can be identified in the field by its conchoidal fracture, opaque appearance, microcrystalline texture, and hardness that scratches glass. Found worldwide in riverbeds, gravel deposits, and hydrothermal vein systems.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Quartz pebble
Silicon dioxide (SiO2)
sedimentary
Fossiliferous Concretion
Septarian Concretion containing Brachiopods/Crinoids
fossil
Generic Pebble / Rock Fragment
Lithic fragment / Weathered rock
sedimentary
Sedimentary Sandstone
Arenite (Sedimentary Rock)
sedimentary
Banded Siltstone / Mudstone Pebble
Siltstone / Argillite
sedimentary