Citrine
Quartz var. Citrine · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Trigonal and Hexagonal; typically massive, granular, or prismatic habit
Mineral Group
Silicates (Tectosilicates)
Chemical Formula
SiO2 (Silicon Dioxide with iron-related color centers or trace ferric iron)
Formation Process
Forms via hydrothermal or magmatic processes at high temperatures (approx. 400-500°C); often results from the presence of iron impurities during the growth of quartz.
About This Crystal
This specimen exhibits a pale to medium golden-yellow hue with a granular to massive surface texture. It is translucent with a vitreous to waxy luster. The shape is irregular and angular, consistent with a rough or broken mineral fragment without defined crystal faces.
Physical Characteristics
Color: Yellow to brownish-orange; Streak: White; Cleavage: None; Fracture: Conchoidal/Sub-conchoidal; Specific Gravity: 2.65; Tenacity: Brittle; Fluorescence: Generally inert under UV light.
Optical Properties
Refractive Index: 1.544-1.553; Birefringence: 0.009 (uniaxial positive); Pleochroism: Weak in pale specimens; No major dispersion.
Hardness & Durability
Origin Region
Notable sources include Brazil (Rio Grande do Sul), Madagascar, Spain, and Russia; typically found in igneous pegmatites or hydrothermal veins.
Hardness & Durability
Mohs Hardness: 7; Toughness: Good (no cleavage); Stable under most conditions, though deep color can fade with prolonged high heat or intense radiation.
Care & Maintenance
Clean with warm soapy water and a soft brush; safe for ultrasonic cleaners in most cases. Store away from intense sunlight to prevent fading and separate from harder stones like Topaz or Sapphire.
Rarity & Value
Natural Citrine is rare; many commercial specimens are heat-treated Amethyst. Value is based on clarity and color intensity. Natural rough specimens are of moderate value for collectors.
Special Characteristics
Contains iron-related color centers. Unlike heat-treated Amethyst (which often has white opaque bases), natural Citrine tends to have a more uniform, dichroic appearance.
Lore & History
Historically known as the 'Merchant's Stone,' it has been used since ancient Greek and Roman times as a decorative gem. Often associated with abundance, manifesting wealth, and the solar plexus chakra in traditional lore.