A furnace for melting aluminium may be built like a brassfounder's furnace; the interior should be square with loose firebars, an ashpit having a grating in front, and a chimney. It must be built of fireclay bricks, puddled with fireclay. The top is covered with a fireclay slab, which may be removed for inserting or withdrawing a crucible or for stoking. The fuel used is ironfounders' coke.