Hertha Metals Hertha Metals is a start-up based in Texas, USA founded in 2022 developing sustainable iron and steel production technology. Hertha Metals has developed a proprietary pyrometallurgical process and high efficiency refining system to produce green steel and high purity iron. Hertha Metals is scaling-up production at its pilot plant to support the production of NdFeB magnets in the USA. Hertha Metals