Conchoidal, Conchoidal, Gemstones of the world (2001) More from other references
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle
SiO 2 · nH 2OGemdat.org , Management Team (2012)
Ca 9(Mg,Fe2+ )(PO 4) 6(PO 3OH)Anthony et al , Handbook of mineralogy (2001)