Yellow Calcite
Calcite var. Yellow Calcite · Semi-Precious Gemstone / Decorative Stone
Crystal System
Trigonal; typically occurs in rhombohedral crystals but shown here in a carved, polished heart shape
Mineral Group
Carbonates (Calcite Group)
Chemical Formula
CaCO3 (Calcium Carbonate) with trace Iron impurities as colorants
Formation Process
Typically sedimentary through chemical precipitation in limestone environments or formed in hydrothermal veins and hot spring deposits
About This Crystal
A polished heart-shaped specimen displaying a warm honey-yellow to lemon-yellow hue. It exhibits a translucent to semi-opaque clarity with a smooth, vitreous to waxy luster. The surface is evenly colored without visible banding or harsh inclusions.
Physical Characteristics
Color: Yellow to Golden; Streak: White; Cleavage: Perfect rhombohedral in 3 directions (though hidden by polish); Fracture: Conchoidal to uneven; Specific Gravity: 2.71; Fluorescence: Often fluoresces pink or red under SW/LW UV light.
Optical Properties
Refractive Index: 1.486 - 1.658; Birefringence: Extremely high (0.172), often exhibiting double refraction in clear specimens; Uniaxial (-)
Hardness & Durability
Origin Region
Mexico (notably Chihuahua), Brazil, and USA; found in various sedimentary environments and carbonate rocks
Hardness & Durability
Mohs Hardness: 3; very soft and fragile. Poor durability for rings; best suited for pendants or display. Highly sensitive to acids.
Care & Maintenance
Clean only with warm soapy water and a soft cloth; avoid ultrasonic cleaners, steam, and all acids (even vinegar). Store separately to prevent scratching by harder stones.
Rarity & Value
Common; very affordable. Value is determined by color intensity and the quality of the carving/polish rather than rarity.
Special Characteristics
High birefringence (double refraction) in transparent pieces; may show phosphorescence or fluorescence under UV light; effervesces (fizzes) in contact with dilute HCl.
Lore & History
Historically used as a source of lime for mortar. In metaphysical practices, it is traditionally associated with the Solar Plexus chakra and believed to enhance self-confidence, mental clarity, and hope.