remelt
/ˌriːˈmɛlt/verb
1 [with object] To melt (a substance, object, etc.) again; to make molten again.
2 [no object] Of a solid substance, object, etc.: to undergo melting again, to revert to a molten state.
Origin
Early 17th century; earliest use found in Francis Bacon (1561–1626), lord chancellor, politician, and philosopher. From re- + melt.