Nosean

Nosean, also known as noselite, is a mineral of the feldspathoid group with formula: Na₈(Al₆Si₆O₂₄)(SO₄)·H₂O.^[1] It forms isometric crystals of variable color: white, grey, blue, green, to brown. It has a Mohs hardness of 5.5 to 6 and a specific gravity of 2.3 to 2.4. It is fluorescent. It is found in low-silica igneous rocks. There is a solid solution between nosean and hauyne, which contains calcium.

Nosean
Nosean crystal group from Ochtendung, Eifel, Germany
General
Category	Tectosilicate minerals, feldspathoid group, sodalite group
Formula	Na8(Al6Si6O24)(SO4)·H2O[1]
IMA symbol	Nsn[2]
Strunz classification	9.FB.10
Crystal system	Cubic
Crystal class	Hextetrahedral (43m) H-M symbol: (4 3m)
Space group	P43m

It was first described in 1815 from the Rhineland in Germany and named after the German mineralogist K. W. Nose (1753–1835). The mineral is rare but widespread, found in such diverse localities as ocean islands (e.g., Tahiti) and the La Sal Range in Utah.