Apatite
What is Apatite?

Apatite is a group of phosphate minerals that includes fluorapatite, chlorapatite, and hydroxylapatite. It’s primarily found in Russia, Mexico, and the USA. Apatite is often used as a gemstone and is popular for its wide range of colors including blue, green, and yellow.
Apatite is a colorful gemstone that comes in a variety of hues. Its vibrant colors and lustrous appearance make it a popular choice for jewelry, especially rings and necklaces.
Chemical Classification | Inorganic - Phosphate |
Color | Apatite comes in a variety of colors, including blue, green, yellow, brown, and colorless. |
Streak | White |
Luster | Vitreous to greasy. |
Transparency | Transparent to translucent. |
Occurrence | Brazil, Mexico, and Myanmar. |
Formation | Apatite forms in various geological environments, including igneous, metamorphic, and sedimentary rocks. |
Diaphaneity | Transparent to translucent |
Cleavage | None |
Mohs Hardness | 5 |
Specific Gravity | 3.16-3.22. |
Diagnostic Properties | Often blue or green, low hardness. |
Chemical Composition | Ca5(PO4)3(F,Cl,OH) |
Pleochroism | Visible in some varieties, especially the blue and green ones. |
Crystal System | Hexagonal |
Optical Properties | Biaxial (-) |
Refractive Index | 1.632 - 1.638 |
Birefringence | 0.002 - 0.008 |
2V angle | Measured: 78° to 82° |
Dispersion | Not notably high. |