| Hiärneite | |
| Category: | Oxide mineral |
| Formula: | (Ca,Mn,Na)2(Zr,Mn3+)5(Sb,Ti,Fe)2O16 |
| Imasymbol: | Hiä[1] |
| Strunz: | 4.DL.10 |
| System: | Tetragonal |
| Class: | Ditetragonal dipyramidal (4/mmm) H-M symbol: (4/m 2/m 2/m) |
| Symmetry: | I41/acd |
| Unit Cell: | a = 15.264 Å, c = 10.089 Å; Z = 8 |
| Color: | Red |
| Habit: | Prismatic, subhedral |
| Cleavage: | None |
| Mohs: | 7 |
| Diaphaneity: | Translucent |
| Gravity: | 5.44 |
| Opticalprop: | Uniaxial (+) |
| Refractive: | nω = 2.120 nε = 2.160 |
| Birefringence: | δ = 0.040 |
| References: | [2] [3] |
Hiärneite is an oxide mineral named after the Swedish geologist Urban Hiärne (1641–1727).[4] The mineral can be found in rocks that mainly consists of fine grained phlogopite. Hiärneite is the first known mineral that contains both of the chemical elements antimony and zirconium.[5] The mineral was described in 1997 for its occurrence in a skarn environment in Långban iron–manganese deposit of the Filipstad district, Värmland, Sweden.[6] [3]