sedimentary

Red Jasper (Skull Carving)

Jasper (Silicon Dioxide, SiO2 plus Iron Oxide inclusions)

Hardness: 6.5-7 (Mohs scale), Color: Opaque brownish-red to deep terracotta, Luster: Vitreous to waxy, Crystal Structure: Microcrystalline/Cryptocrystalline (Trigonal), Cleavage: None (conchoidal fracture), Specific Gravity: 2.58-2.91

Hardness: 6

Identified March 3, 2026More sedimentary →

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 from hydrothermal fluids or in sedimentary environments where volcanic ash or fine-grained sediments are silicified. The red color is caused by the inclusion of iron oxide (hematite).

Uses & applications

Primarily used for lapidary work including carvings (such as skulls), beads, cabochons, and decorative ornamental objects. Historically used for seals and amulets.

Geological facts

Red Jasper is often known as the 'Stone of Endurance' in metaphysical circles. In ancient Egypt, it was associated with the blood of Isis and was used for amulets of protection. Because it is a form of chalcedony, it is incredibly durable and holds a high polish.

Field identification & locations

Can be identified by its deep red, opaque appearance and high hardness (it cannot be scratched by a steel knife). Commonly found in Australia, Brazil, India, South Africa, and the United States (notably the Southwest and Pacific Northwest).

Other sedimentary specimens

See all

Sandstone or Siltstone

Arenite (if sandstone)

Sedimentary

Sandstone

Arenite (primarily SiO2)

sedimentary

Shale or Slaty Mudstone

Argillaceous sedimentary rock

sedimentary

Chert Breccia

Brecciated Chert (Microcrystalline Silica)

sedimentary

Sandstone (Quartz-rich)

Arenite (SiO2)

sedimentary

Sandstone (with man-made markings)

Arenite (composed primarily of Quartz, SiO2)

sedimentary