This is the final product of a tin concentration plant, consisting of crushed, washed and separated cassiterite. It takes the form of a heavy, dark powder resembling fine black sand. Smelters require this high-grade concentrate to efficiently extract metallic tin without wasting energy on waste rock.
Heard on the job
We shipped forty tons of black tin from the concentrator this week.
Insider tip
The name comes from its dark color after washing, distinguishing it from white tin, which is the refined metal.