Sweetwater Gypsum Plant, Texas

This is one of a few US Gypsum mines and wallboard plants in the USA. The company presented its Sheetrock brand of wallboard at the 1933 Chicago World’s Fair, and since then it has been among the largest suppliers of gypsum-based housing products in the country. It has seven other gypsum mines (in Utah, Oklahoma, Michigan, Indiana, Iowa, and at Plaster City, California), and fifteen wallboard plants in the USA.