Red Jasper
Microcrystalline Quartz var. Jasper · Semi-Precious Gemstone / Decorative Stone
Crystal System
Trigonal (microcrystalline); usually occurs in massive form without visible external crystal faces.
Mineral Group
Silicates (Tectosilicate subgroup)
Chemical Formula
SiO2 with Fe2O3 (Iron Oxide) inclusions
Formation Process
Forms via the deposition of silica from hydrothermal solutions or within volcanic and sedimentary rocks. Its opacity is due to high mineral impurity content (up to 20%).
About This Crystal
A dense, opaque variety of chalcedony with a dull to vitreous luster. This specimen is carved into a frog, showing a dusty brick-red to terracotta base color with white/grey chalcedony veining and mottled patterns.
Physical Characteristics
Color: Brick red; Streak: White; Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.58-2.91; Tenacity: Brittle; Fluorescence: Generally inert.
Optical Properties
Refractive Index: 1.544-1.553; Opaque (no light passes through except on very thin edges); No pleochroism or dispersion visible due to opacity.
Hardness & Durability
Origin Region
Notable sources include Brazil, South Africa, India, USA (Oregon, California), and Australia. Found in sedimentary and metamorphic environments.
Hardness & Durability
Mohs Hardness: 6.5-7.0. Very durable and tough due to its microcrystalline structure, making it excellent for carvings and daily wear.
Care & Maintenance
Clean with warm soapy water and a soft brush. Generally safe for ultrasonic cleaners. Avoid harsh chemicals and sudden extreme temperature changes which might cause cracks in veins.
Rarity & Value
Common and readily available. Value is determined by the quality of the carving, color saturation, and the aesthetic of internal veining or patterns. Usually very affordable.
Special Characteristics
Features distinct white or grey quartz veining (brecciated appearance) and a smooth, matte-to-waxy finish when polished. Carving features inlaid black eyes (likely glass or hematite).
Lore & History
Historically known as the 'Stone of Endurance' and used in ancient amulets for protection. In metaphysical traditions, it is associated with the Root Chakra and believed to provide grounding, courage, and stability.