nigerite
/ˈnʌɪdʒərʌɪt/Mineralogy
noun
A hydroxide and oxide of zinc, iron, magnesium, tin, and aluminium, crystallizing in the hexagonal system and occurring as brown or red platelets; (Zn,Fe2+,Mg)(Sn,Zn)2(Al,Fe3+)12O22(OH)2.
Origin
1940s. From niger- + -ite.