kəˈsid.əˌrīt noun
( -s )
Etymology: French cassitérite, from Greek kassiteros tin + French -ite
: a brown or black mineral that consists of tin dioxide SnO 2 , is the chief source of metallic tin, and occurs in tetragonal crystals of brilliant adamantine luster and also in massive forms sometimes (1) compact with concentric fibrous structure resembling wood and sometimes (2) in rolled or pebbly fragments (hardness 6-7, specific gravity 6.8-7.1) — called also respectively (1) wood tin (2) stream tin