< Editing Internet Texts < Gemstones _1.jpg.webp)
Apatite
A great resemblance of apatite to such minerals as beryl or olivine misled many mineralogists in the past, and it is still often mistaken for other minerals. Its name is derived from a Greek word απατείν (apatein), which means to deceive.[1]
Apatite is actually a name of a whole group of minerals, not only one.[1] Its chemical formula which includes fluorine, chlorine, and hydroxide indicates that those three elements can substitute for each other in different proportions.
Apatite crystals have many color varieties: green to yellow and purple to blue. Some crystals can also be transparent or multicolored.
Apatite
Basic properties
| Composition | (Ca,Ba,Pb,Sr)5(PO4,CO3)3(F,Cl,OH) |
| Class | Phosphates |
| Crystal system | Hexagonal |
| Mohs' hardness | 5 |
| Fracture | Conchoidal |
| Cleavage | None |
| Lustre | Glassy to resinous |
| Streak | White to grey |
| Localities | Portugal, Mexico, Switzerland, Russia, Brazil, Pakistan, Afghanistan, Germany, Canada |
References
This article is issued from Wikiversity. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.