Platinum crucible, with reinforced rim

Platinum labware has excellent resistance to acids such as acetic, hydrochloric, hydrofluoric, hydroiodic, nitric, selenic, and sulfuric, and to oxidation at high temperatures. These platinum crucibles can be cleaned by boiling in a suitable solvent, for the removal of substances which have alloyed with the surface, scour with alumina powder. Having a reinforced rim means that the rim of the crucible is thicker than the walls to make it stronger; this is where the crucible can be gripped if tongs are used during the handling process.