ConchoidalWalter Schumann, Gemstones of the world (2001), ConchoidalWalter Schumann, Gemstones of the world (2001)
Uneven, Uneven, ConchoidalGemdat.org, Management Team (2012)
CaTiSiO 5Ulrich Henn and Claudio C.
Mn 3Al 2(SiO 4) 3Arthur Thomas , Gemstones (2009)