Hafnon
| Hafnon | |
|---|---|
| Very small brown single crystals of hafnon from Bernic Lake, Lac-du-Bonnet District, Manitoba, Canada | |
| General | |
| Category | Nesosilicates | 
| Formula | HfSiO4 | 
| IMA symbol | Haf | 
| Strunz classification | 09.AD.30 | 
| Dana classification | 51.05.02.02 | 
| Crystal system | Tetragonal | 
| Crystal class | Ditetragonal Dipyramidal (4/mmm ) H-M symbol: (4/m 2/m 2/m) | 
| Space group | I41/amd | 
| Unit cell | a = 6.5725(7) Å, c = 5.9632(4) Å=; Z = 4 | 
| Identification | |
| Colour | Orange-red,brownish yellow, rarely colourless | 
| Crystal habit | Euhedral to irregular crystals | 
| Cleavage | {???} Indistinct | 
| Mohs scale hardness | 7.5 | 
| Luster | Vitreous | 
| Streak | grey white | 
| Diaphaneity | Transparent | 
| Density | 6.97 | 
| Optical properties | Uniaxial (+) | 
| Refractive index | nω = 1.930 - 1.970 nε = 1.980 - 2.030 | 
| Birefringence | δ = 0.050 | 
| Common impurities | Often zoned with zircon. Forms part of zircon-hafnon series | 
Hafnon is a hafnium nesosilicate mineral with the idealized chemical formula HfSiO4. It is the mineral form of Hafnium silicate and one of the few known minerals with essential hafnium.