Carnelian Agate
Quartz var. Carnelian Agate · Semi-Precious Gemstone and Decorative Stone
Crystal System
Trigonal, microcrystalline cryptocrystalline quartz habit forming in nodules and rounded masses
Mineral Group
Silicates (Subgroup: Tectosilicate)
Chemical Formula
SiO2
Formation Process
Hydrothermal and sedimentary deposition filling cavities in volcanic rocks via silica-rich solutions over long periods
About This Crystal
A polished, rounded cabochon showing translucent to opaque areas with distinctive reddish-orange banding and milky-white chalcedony patterns. The surface has a smooth, highly reflective vitreous to waxy luster.
Physical Characteristics
Body color ranges from milky white and grey to reddish-brown and orange bands. White streak, conchoidal fracture, no distinct cleavage, and a specific gravity around 2.65.
Optical Properties
Uniaxial positive with double refraction, generally low birefringence masked by microcrystalline structure, vitreous luster.
Hardness & Durability
Origin Region
Found globally with notable sources in India, Brazil, Madagascar, and the United States, typically in volcanic cavities and hydrothermal veins
Hardness & Durability
Mohs hardness of 6.5 to 7, good toughness making it durable and very suitable for daily jewelry wear.
Care & Maintenance
Safe to clean with warm soapy water. Avoid harsh chemical cleaners and prolonged exposure to direct sunlight to preserve color vibrancy.
Rarity & Value
Common and widely accessible, with value depending on color saturation, banding clarity, and polish quality. Common treatments include mild heat enhancement or dyeing.
Special Characteristics
Features distinct microcrystalline banding and iron-oxide staining creating vibrant reddish patterns within a translucent chalcedony matrix.
Lore & History
Historically used in ancient civilizations like Egypt and Rome for seals, signet rings, and talismans. In modern crystal lore, it is associated with vitality, motivation, and the sacral chakra, though these remain traditional beliefs rather than scientific claims.