Apatite (Blue Apatite)
Hydroxyapatite / Fluorapatite / Chlorapatite · Semi-Precious Gemstone / Collector Mineral
Crystal System
Hexagonal system; typically forms as prismatic crystals with hexagonal cross-sections, but often found in massive or tumbled/rolled forms.
Mineral Group
Phosphates (Apatite Group)
Chemical Formula
Ca5(PO4)3(F,OH,Cl)
Formation Process
Formation occurs primarily through magmatic processes in igneous rocks (pegmatites) or as a secondary mineral in metamorphic rocks. It also occurs in sedimentary environments as biological phosphate.
About This Crystal
The specimen is a tumbled/polished stone displaying a deep teal-to-navy blue color. It features a vitreous to slightly sub-resinous luster and is translucent to opaque. It shows characteristic internal fracturing and white-to-yellowish veining or inclusions typical of the species.
Physical Characteristics
Color: Teal/Deep Blue; Streak: White; Cleavage: Poor in one direction; Fracture: Conchoidal to uneven; Specific Gravity: 3.16 – 3.22; Fluorescence: Often fluoresces yellow or violet-blue under shortwave UV light.
Optical Properties
Refractive Index: 1.63 - 1.64; Birefringence: 0.002 - 0.008; Pleochroism: Strong (deep blue to colorless/yellowish); Optical Nature: Singly refractive (uniaxial negative).
Hardness & Durability
Origin Region
Notable sources include Madagascar (highly sought for neon-blue colors), Brazil, Mexico, Myanmar, and Sri Lanka. Found primarily in pegmatites and metamorphic rocks.
Hardness & Durability
Mohs Hardness: 5 (Defining mineral for 5 on the scale); Toughness: Low/Brittle; Heat and acid sensitive. Not recommended for rings; better suited for pendants or earrings.
Care & Maintenance
Clean only with warm, soapy water; avoid ultrasonic or steam cleaners. Store separately from harder minerals like quartz or sapphire to prevent scratching. Keep away from acids and prolonged high heat.
Rarity & Value
Common mineral but gem-quality specimens are uncommon. Value is determined by color intensity (Neon 'Paraíba' blue is most valued) and clarity. Often untreated, though occasionally heat-treated to enhance blue tones.
Special Characteristics
Known for intense 'electric' blue shades that can mimic Paraíba tourmaline. It is the main mineral found in human teeth and bone, though the gemstone variety is concentrated and crystallized.
Lore & History
Historically used as an ore of phosphorus. The name is derived from the Greek 'apate,' meaning 'to deceive,' because it was frequently confused with other minerals like tourmaline. Metaphysically associated with the Throat Chakra, communication, and appetite suppression.