Red Jasper
Jasper (Silicon Dioxide, SiO2)
Rock Type: sedimentary

Physical Properties
Hardness: 6.5-7 (Mohs scale); Color: Red (due to iron inclusions); Luster: Vitreous to dull; Crystal Structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91
Formation & Geological History
Formed through the infiltration of silica-rich fluids into volcanic ash or fine-grained sediments. It often forms in hydrothermal environments or through the replacement of organic materials.
Uses & Applications
Used primarily for ornamental purposes, jewelry (cabochons), lapidary art, and metaphysical practices. Historically used for tools and arrowheads due to its hardness.
Geological Facts
Ancient Egyptians often wore red jasper amulets for protection. It is a variety of chalcedony and gets its deep red color primarily from hematite (iron oxide) impurities trapped within the silica.
Field Identification & Locations
Identify in the field by its waxy to dull luster, extreme hardness (it will scratch glass), and opaque nature even at thin edges. Look for smooth, shell-like (conchoidal) fractures on broken surfaces.
Identified on: 4/18/2026
Mode: Standard