Iron(II) sulfate was used in the textile industry for centuries as a dye fixative. It is used historically to blacken leather and as a constituent of ink. The preparation of sulfuric acid ('oil of vitriol') by the distillation of green vitriol (Iron(II) sulfate) has been known for at least 700 years. Together with other iron compounds, ferrous sulfate is used to fortify foods and to treat and prevent iron deficiency anemia. Constipation is a frequent and uncomfortable side effect associated with the administration of oral iron supplements. Stool softeners often are prescribed to prevent constipation. Ferrous sulfate was used in the manufacture
Utah oil sands Tar Sand Triangle, the highest deposit. The Tar Sand Triangle is located in Southeastern Utah and covers an area of . It is located between the Dirty Devil and Colorado Rivers in Wayne and Garfield Counties. The Tar Sand Triangle is the largest deposit of oil sands in the United States known today. It contains about 6.3 billion barrels of heavy oil, but is thought to have originally held more. At one point the Tar Sand Triangle could have consisted of 16 billion barrels of heavy oil, almost as much as in Utah today. Utah oil sands In the United