sedimentary

Jasper (Red/Yellow Jasper Pebble)

Silicon Dioxide (SiO2 with Iron Oxide inclusions)

Hardness: 6.5 to 7 on the Mohs scale. Color: Opaque reddish-brown to orange-yellow. Luster: Waxy to dull (smooth polished pebble surface). Crystal structure: Trigonal (microcrystalline quartz). Cleavage: None, exhibits conchoidal fracture.

Hardness: 6
Color: Opaque reddish-brown to orange-yellow
Luster: Waxy to dull (smooth polished pebble surface)

Identified July 27, 2026More sedimentary →

Explore Jasper (Red/Yellow Jasper Pebble) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed through the deposition of silica-rich fluids filling cavities or sedimentary rocks, often enriched with iron oxide impurities during diagenesis or hydrothermal activity.

Uses & applications

Commonly used for lapidary work, decorative rock collections, tumbled stones, jewelry beads, and cabochons.

Geological facts

Jasper is a microcrystalline variety of quartz. Its vibrant earthy red and yellow colors are caused by varying amounts of iron oxides (hematite or goethite) within the silica matrix.

Field identification & locations

Identified in the field by its opacity, hardness (cannot be scratched by a steel knife), and smooth, water-worn rounded pebble shape. Found in riverbeds, gravel deposits, and sedimentary basins worldwide.

Other sedimentary specimens

See all

Sandstone or Siltstone

Arenite (if sandstone)

Sedimentary

Sedimentary Sandstone

Arenite (Sedimentary Rock)

sedimentary

Fossiliferous Concretion

Septarian Concretion containing Brachiopods/Crinoids

fossil

Banded Siltstone / Mudstone Pebble

Siltstone / Argillite

sedimentary

Shale

Shale (clastic sedimentary rock)

sedimentary

Shale

Sedimentary Shale

sedimentary