Some Chinese cookware is seasoned at a much higher temperature than conventional seasoning at 450 °C. More akin to bluing, this type of seasoning mainly involves a chemical change of the iron pan itself and not the oil. When beef tallow is heated at this temperature, it evaporates on the iron surface and increases the partial pressure of O (oxygen gas) on the pot surface. This transport of oxygen encourages the formation of FeO nanoballs. The surface formed is broadly speaking hydrophobic and oleophilic, but is more versatile in that it temporarily turns hydrophilic on contact with high-water ingredients.