Carnelian
Quartz var. Carnelian · Semi-Precious Gemstone
Crystal System
Trigonal, typically forms as microcrystalline aggregates (chalcedony) with a cryptocrystalline habit
Mineral Group
Silicates (Tectosilicate subgroup)
Chemical Formula
SiO2
Formation Process
Low-temperature hydrothermal deposition or groundwater percolation in silica-rich volcanic cavities and sedimentary rock
About This Crystal
Small, transparent to translucent, brilliantly faceted beads with a vibrant reddish-orange color and a vitreous luster
Physical Characteristics
Vibrant orange to reddish-orange color, white streak, conchoidal fracture, no distinct cleavage, specific gravity of approximately 2.65, brittle tenacity
Optical Properties
Singly refractive appearance due to microcrystalline nature with an average refractive index of 1.543 to 1.553, uniaxial positive optical character
Hardness & Durability
Origin Region
India, Brazil, Madagascar, Uruguay, and the United States; typically forms in volcanic and sedimentary rocks
Hardness & Durability
Mohs hardness of 7, good durability, tough and suitable for everyday jewelry wear, resistant to scratching by most common materials
Care & Maintenance
Clean with warm soapy water and a soft brush, avoid harsh chemicals or prolonged exposure to extreme heat, generally stable in sunlight
Rarity & Value
Common and widely available, value is relatively low for standard beads but increases with exceptional color saturation, transparency, and size
Special Characteristics
Often heat-treated to enhance or deepen the natural orange and red coloration by oxidizing trace iron impurities within the chalcedony structure
Lore & History
Historically used in ancient civilizations like Egypt, Rome, and Greece for signet rings and amulets; traditionally associated with courage, motivation, and vitality in crystal healing practices