Carnelian
Quartz var. Carnelian (Chalcedony) · Semi-Precious Gemstone
Crystal System
Trigonal/Hexagonal; Cryptocrystalline (microscopic fibers, no visible crystal faces)
Mineral Group
Silicates (Tectosilicate)
Chemical Formula
SiO2 (Silicon Dioxide) with Fe2O3 (Iron Oxide) impurities
Formation Process
Hydrothermal; forms from low-temperature silica-rich fluids filling cavities in volcanic rocks.
About This Crystal
Small, brownish-red translucent fragment with a waxy to vitreous luster and uneven surface texture.
Physical Characteristics
Color: Reddish-brown; Streak: White; Fracture: Conchoidal; Specific Gravity: 2.58–2.64; Luster: Waxy.
Optical Properties
Refractive Index: 1.530–1.540; Birefringence: ~0.004; Diaphaneity: Translucent to opaque.
Hardness & Durability
Origin Region
India, Brazil, Uruguay, Madagascar; typically found in weathered volcanic outcrops.
Hardness & Durability
Mohs Hardness: 6.5–7; Excellent toughness due to interlocking micro-structure; very durable for wear.
Care & Maintenance
Wash with warm soapy water and a soft brush; avoid harsh chemicals and extreme heat.
Rarity & Value
Common; value depends on color saturation and clarity; heat treatment of pale stones is frequent.
Special Characteristics
Translucency varies when backlit; color-banding may be present (grading into agate).
Lore & History
Ancient Egyptians used it for protection and vitality; traditionally associated with the Sacral Chakra.