Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Rock Type: sedimentary

Physical Properties
Hardness: 6.5-7 (Mohs scale); Color: Deep reddish-brown to brick red; Luster: Vitreous to waxy (when polished); Crystal structure: Hexagonal (trigonal) microcrystalline; Cleavage: None, conchoidal fracture; Specific gravity: 2.58-2.91.
Formation & Geological History
Formed through the accumulation of fine-grained silica particles, typically originating from volcanic ash or sediment, which are then subject to hydrothermal activity or diagenesis where iron impurities provide the red pigmentation.
Uses & Applications
Commonly used for lapidary work, jewelry (beads, cabochons), ornate carvings, and as a popular tumbled stone for crystal healing and mineral collectors.
Geological Facts
Red Jasper has been used since antiquity as a sacred stone; it was known as the 'mother of all stones' in some cultures and was used in the breastplate of the High Priest in Biblical times.
Field Identification & Locations
Identify in the field by its opaque reddish appearance and extreme hardness (it will scratch glass). It is often found in riverbeds or as nodules in sedimentary rocks. Common locations include India, Brazil, the USA (southwest), and South Africa.
Identified on: 4/23/2026
Mode: Standard