The techniques for making cast iron have not changed much since the early part of the 19th century. In metallurgy, cast iron is an iron alloy with a carbon content of 2.1 to 6.67%. The GHM foundry can also process aluminium and bronze alloys. The molten metal at 2,553°F (1 400°C) or even 2,732°F (1 500°C) is transported to the casting site in a ladle, or ‘belon’. Once the belon is tilted, the metal quickly fills the moulds in a fairy tale of colours from milky yellow to orange. The liquid metal is poured down to the vent (overflow) which is lit to release the gases.