Citrine
Quartz var. Citrine · Semi-Precious Gemstone
Crystal System
Trigonal, prismatic habit with typical hexagonal cross-sections
Mineral Group
Silicates (Tectosilicate subgroup)
Chemical Formula
SiO2
Formation Process
Hydrothermal and igneous processes, often forming in pegmatites, granitic cavities, and hydrothermal veins at moderate temperatures
About This Crystal
A translucent to transparent yellowish-brown to golden quartz crystal fragment, displaying vitreous luster and distinct internal fracture planes with white quartz matrix inclusions
Physical Characteristics
Color ranges from pale yellow to deep amber-brown; white streak; no cleavage; conchoidal fracture; specific gravity of 2.65; brittle tenacity; exhibits strong piezoelectric properties
Optical Properties
Singly or weakly doubly refractive with a low birefringence of 0.009; refractive index of 1.544 to 1.553; uniaxial positive optical sign; weak or absent pleochroism
Hardness & Durability
Origin Region
Brazil, Madagascar, Bolivia, and the Ural Mountains in Russia; formed in pegmatites and hydrothermal veins
Hardness & Durability
Mohs hardness of 7; good durability for daily wear in jewelry with no cleavage planes, though vulnerable to severe impact and thermal shock
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid harsh chemicals, ultrasonic cleaners, and prolonged direct sunlight to prevent color fading
Rarity & Value
Common to moderately rare for natural untreated stones; heavily valued for rich golden colors; most commercial citrine is heat-treated amethyst
Special Characteristics
Exhibits piezoelectric and pyroelectric properties; internal fractures produce bright light reflections; trace amounts of iron ions account for the yellow-to-brown coloration
Lore & History
Historically known as the merchant's stone for attracting wealth and abundance; associated with the solar plexus chakra in metaphysical traditions for promoting vitality and personal power