Uneven, Irregular, Management Team (2012)
Splintery, Granular, Splintery, Granular, Gemstones (2009)
(Mg,Fe2+ ) 3Si 2O 5(OH) 4Anthony et al , Handbook of mineralogy (2001)
Ca 2(Mg,Fe) 5(OH) 2Walter Schumann , Gemstones of the world (2001) More from other references