Citrine
Quartz var. Citrine · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Trigonal; typically occurs in hexagonal prisms or as massive/lithic fragments in rough form.
Mineral Group
Silicates (Tectosilicate)
Chemical Formula
SiO2 (Silicon Dioxide with trace Fe3+ impurities)
Formation Process
Primarily hydrothermal in quartz veins or as a late-stage crystallization in pegmatites.
About This Crystal
An orangey-yellow specimen with a vitreous (glassy) luster. It exhibits a translucent to transparent body with visible internal fracturing and conchoidal features on the surface.
Physical Characteristics
Color: Yellow to amber; Streak: White; Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.65; Fluorescence: Generally inert.
Optical Properties
Refractive Index: 1.544-1.553; Birefringence: 0.009; Doubly refractive; No significant pleochroism.
Hardness & Durability
Origin Region
Rio Grande do Sul, Brazil; Madagascar; Spain; and the Ural Mountains of Russia.
Hardness & Durability
Mohs Hardness: 7; Toughness: Good; Highly durable and suitable for all jewelry types.
Care & Maintenance
Clean with warm soapy water. Stable to most chemicals, but should be kept away from prolonged direct sunlight to prevent fading.
Rarity & Value
Relatively common; natural untreated citrine is rare, while most commercial citrine is heat-treated amethyst. Value is determined by color saturation and clarity.
Special Characteristics
Exhibits piezoelectric and pyroelectric properties; this specimen shows internal 'rainbows' due to light interference in fractures.
Lore & History
Known historically as the 'Merchant's Stone' for its association with prosperity. Ancient Greeks used it as a decorative gem as early as the Hellenistic Age.