sedimentary/mineral

Red Jasper (River Pebble)

Silicon Dioxide (SiO2) with iron oxide inclusions

Hardness: 6.5-7 (Mohs); Color: Brick red to brownish-red; Luster: Dull to waxy; Crystal structure: Microcrystalline (trigonal); Cleavage: None; Specific Gravity: 2.5-2.9.

Hardness: 6
Color: Brick red to brownish-red
Luster: Dull to waxy

Identified July 20, 2026More sedimentary/mineral →

Explore Red Jasper (River Pebble) in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Hardness: 6.5-7 (Mohs); Color: Brick red to brownish-red; Luster: Dull to waxy; Crystal structure: Microcrystalline (trigonal); Cleavage: None; Specific Gravity: 2.5-2.9.

Formation & geological history

Formed from the deposition of silica in hydrothermal veins or as a chemical precipitate in sedimentary environments. Its red color is derived from high hematite (iron) content. The tumbled shape indicates erosion in a high-energy water environment like a river or beach.

Uses & applications

Used primarily in lapidary work for cabochons, beads, and decorative stones. Historically used for seals, jewelry, and as a protective talisman.

Geological facts

Jasper is an opaque variety of chalcedony. In ancient times, red jasper was known as the 'stone of endurance' and was used by Egyptian artisans and Greek warriors for strength.

Field identification & locations

Identify by its opacity (even when held to light), smooth texture when weathered, and deep red streak. Commonly found in riverbeds and gravel pits globally, especially in areas with volcanic or sedimentary history.

Other sedimentary/mineral specimens

See all

Sandstone (Picture Sandstone)

Arenite (primarily SiO2)

sedimentary

Pyrite

Iron Sulfide (FeS2)

mineral

Sedimentary Sandstone with Iron Oxide

Ferruginous Sandstone

sedimentary

Blue Apatite

Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)

mineral

Limonite Geode (Ironstone Concretion)

Limonite [FeO(OH)·nH2O] with possible Quartz or Calcite interior

sedimentary

Brown Sandstone (River Rock)

Arenite

sedimentary