... etc 2.melting such metals as copper, gold ,silver, zinc, aluminium Graphite crucible have four different main ... crucible , different using .If FOR metling copper, gold ,silver, zinc, aluminium , lead , cast iron .etc Always ... suitable for melting such metals as copper, gold ,silver, zinc, aluminium , lead , cast iron .etcAnd ... Item 2 . sic graphite crucible for Aluminum , cooper.etc smelting crucible