Nosean
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Nosean, also known as Noselite, is a mineral of the feldspathoid group with formula: Na8Al6Si6O24(SO4). 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.
It was first described in 1815 from th 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.