sedimentary

Jasper-Agate Breccia

Silicon Dioxide (SiO2) with iron oxide inclusions

Hardness: 6.5-7 (Mohs scale); Color: Ochre, rust red, and translucent white; Luster: Vitreous/Waxy; Crystal Structure: Cryptocrystalline/Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Color: Ochre, rust red, and translucent white
Luster: Vitreous/Waxy

Identified March 11, 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 by the deposition of silica-rich fluids into cavities or fractures in host rock. These fluids cement together broken fragments of jasper and chalcedony. Many high-quality specimens date from the Cenozoic era or older, typically found in volcanic regions or ancient riverbeds.

Uses & applications

Commonly used in lapidary arts for cabochons, pendants, and decorative carvings. It is also favored by mineral collectors for its unique mosaic-like patterns.

Geological facts

Brecciated stones are naturally 'healed' by geological processes where earth movements break the stone and mineralized silica acts as a glue, creating a distinct patchwork appearance. No two pieces are ever identical.

Field identification & locations

Identify by its multi-colored, angular fragments bonded by a different colored matrix. It is found globally, with significant deposits in the USA (Oregon, Idaho), Madagascar, and Brazil. Collectors look for sharp contrast and high polish.

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