Strunz classification 9.BC.05 Space group C2/m | Formula(repeating unit) (Sc,Y)2Si2O7 Crystal system Monoclinic | |
 | ||
Crystal class Prismatic (2/m)(same H-M symbol) | ||
Thortveitite is a mineral consisting of scandium yttrium silicate (Sc,Y)2Si2O7. It is the primary source of scandium. Occurrence is in granitic pegmatites. It was named after Olaus Thortveit, a Norwegian engineer. It is grayish-green, black or gray in color.
A transparent gem quality example was found in 2004, and reported in "The Journal of Gemmology", 2008 Volume 31.
References
Thortveitite Wikipedia(Text) CC BY-SA