Spessartine
Formula: Na(AlSi3O8)
Species: Silicates – (Nesosilicates)
Colour: White to grey, bluish, greenish, reddish, colorless
Lustre: Vitreous
Hardness: 6 – 6½
Specific Gravity: 2.6 – 2.65
Crystal System:Triclinic
Member of: Plagioclase Group > Feldspar Group
Name: Named in 1815 by Johan Gottlieb Gahn and Jöns Jacob Berzelius from Latin “albus”, white, alluding to its usual color.
Co-Type Localities: Catharina Neufang Mine, St Andreasberg, Braunlage, Goslar District, Lower Saxony, Germany, Finnbo (Finbo), Falun, Dalarna County – Sweden
One of the most common members of the Feldspar group. Often associated with potassium feldspar (triclinic microcline or monoclinic orthoclase), with which it may form epitaxial intergrowths.