noun
or plat·i·nite ˈplad.əˌnīt
( -s )
Etymology: Swedish platynit, from Greek platynein to widen, flatten (from platys broad, flat) + Swedish -it -ite — more at place
: a mineral PbBi 2 (Se,S) 3 consisting of a lead and bismuth selenide and sulfide and occurring in thin iron-black metallic plates