Iron Oxide - Black
Iron Oxide - Black FeO Ferrous Oxide (BA510)
Having a higher iron content than red iron oxide (natural or Synthetic), it produces darker shades of colour (4-8%).
The final colour obtained with iron oxide varies with the type of glaze, firing temperature and kiln atmosphere.
Iron oxide is also an active flux in glazes and even in small amounts will make a glaze noticeably more fluid.