Blue Calcite
Calcite · Mineral Specimen and Decorative Stone
Crystal System
Trigonal, typically occurring in massive, rhombohedral, or cleavage-fragment habits
Mineral Group
Carbonates
Chemical Formula
CaCO3
Formation Process
Sedimentary precipitation, low-temperature hydrothermal veins, and metamorphic recrystallization of limestone
About This Crystal
The specimen is a pale blue, translucent to transparent massive crystal chunk with prominent cleavage planes, exhibiting a vitreous to pearly luster and internal fractures that refract light into faint rainbow flashes.
Physical Characteristics
Light blue body color with a white streak, perfect rhombohedral cleavage in three directions at roughly 75 degrees, uneven to conchoidal fracture, specific gravity around 2.71, brittle tenacity, and often exhibits strong pink to red fluorescence under shortwave UV light.
Optical Properties
Uniaxial negative with very high birefringence, leading to strong double refraction easily visible through transparent sections, and a refractive index ranging from 1.486 to 1.658.
Hardness & Durability
Origin Region
Madagascar, Mexico, and the USA; forms in sedimentary, metamorphic, and hydrothermal environments
Hardness & Durability
Mohs hardness of 3, making it very soft and easily scratched by a copper coin; it has poor toughness due to perfect cleavage and is extremely sensitive to acids.
Care & Maintenance
Clean only with a soft, damp cloth; avoid all acids, vinegar, and harsh chemical cleaners; do not use ultrasonic cleaners or steam, and store separately to prevent scratching.
Rarity & Value
Common mineral, though high-clarity blue specimens are popular; value is generally low to moderate depending on size and color intensity, with no common artificial treatments.
Special Characteristics
Strong double refraction (birefringence), perfect rhombohedral cleavage, and potential fluorescence under ultraviolet light.
Lore & History
Often associated with calming energy, emotional release, and the throat chakra in modern crystal healing traditions, though these are symbolic beliefs without scientific backing.