Fluorite
Fluorite (IMA: Fluorite) · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Cubic (Isometric); typically cubes or octahedrons; massive or granular in commercial tumbles
Mineral Group
Halides
Chemical Formula
CaF2 (Calcium Fluoride) with rare earth elements as chromophores (e.g., Ce, Y, Fe)
Formation Process
Hydrothermal; originating in low to high temperature veins, often associated with lead and silver ores
About This Crystal
Multi-colored (Rainbow) translucent stone with color zoning of green, yellow, and purple; vitreous luster; smooth tumbled surface with internal fractures
Physical Characteristics
Color: Mixed green/purple/yellow; Streak: White; Cleavage: Perfect octahedral in four directions; SG: 3.18; Fluorescence: Strong blue-violet under UV
Optical Properties
Singly refractive (isotropic); Refractive Index: 1.434; Low dispersion; lacks pleochroism due to cubic structure
Hardness & Durability
Origin Region
China, Mexico, South Africa, UK (Blue John), and USA (Illinois)
Hardness & Durability
Mohs Hardness: 4; Brittle; Low toughness; poor wearability for heavy-duty jewelry like rings
Care & Maintenance
Wash with warm soapy water; avoid ultrasonic or steam; keep away from acids; store separately to avoid scratches from harder stones; light sensitive
Rarity & Value
Common; Value based on color intensity and zoning; often untreated but occasionally coated for surface luster
Special Characteristics
Pronounced color saturation zoning and strong fluorescence under ultraviolet light (the namesake for the term fluorescence)
Lore & History
Historically used by Ancient Egyptians in scarabs; traditionally associated with mental clarity, concentration, and balancing the third eye chakra