Look up crucible in Wiktionary, the free dictionary.
A modern crucible used in the production of silicon ingots via the Czochralski processSmaller clay graphite crucibles for copper alloy melting
A crucible is a container in which metals or other substances may be melted or subjected to very high temperatures. Although crucibles have historically tended to be made out of clay,[1] they can be made from any material that withstands temperatures high enough to melt or otherwise alter its contents.
^Percy, John. Natural Refractory Materials Employed in the Construction of Crucibles, Retorts, Forunaces &c. Metallurgy. London: W. Clowes and Sons, 1861. 208–09. Print.