Nosean
Mineral Na8Al6Si6O24(SO4)·H2O
Also called Noselite
About it
Grey to brown or blue dodecahedra in phonolite and other silica-poor volcanic rocks, best known around Laacher See in Germany's Eifel; a sulphate member of the sodalite group.
- Type
- Mineral
- Group
- Silicate (tectosilicate), sodalite group
- Formula
- Na8Al6Si6O24(SO4)·H2O
- Hardness (Mohs)
- 5.5–6
- Specific gravity
- 2.3–2.4
- Streak
- white
- Lustre
- vitreous (glassy)
- Crystal system
- Isometric (cubic)
- Colours
- grey, brown, blue, white, colourless, black
- Transparency
- transparent, translucent, opaque
- Cleavage and fracture
- indistinct dodecahedral; uneven fracture
Typical values: real specimens vary. For more, see mindat.org.