Iron ore
In cast iron sulfur promotes the formation of white iron. As little as 0.5% can counteract the effects of slow cooling and a high silicon content . White cast iron is more brittle, but also harder. It is generally avoided, because it is difficult to work, except in China where high sulfur cast iron, some as high as 0.57%, made with coal and coke, was used to make bells and chimes . According to , good foundry iron should have less than 0.15% sulfur. In the rest of the world a high sulfur cast iron can be used for making castings, but will make poor wrought iron.
Cast-iron cookware
However, cast iron has seen a resurgence of its popularity in specialty markets. Through cooking shows, celebrity chefs have brought renewed attention to traditional cooking methods, especially the use of cast iron. In the 2010s, small startup companies such as FINEX, Element Cookware, Smithey Ironware Company, Marquette Castings, Stargazer Cast Iron and Borough Furnace began producing cast-iron cookware designs for specialty cooking markets.