Great Northern Iron Ore Properties principal activity is to conduct operations through leasing and maintenance of certain mineral and nonmineral lands owned by the trust on the Mesabi Range of Minnesota. The company is a conventional trust organized under the laws of the state of Michigan. It is involved solely with the leasing and care of these properties. The company owns mineral interests in more than 12,000 acres on the Mesabi Iron Formation, which includes approximately 7,450 acres that are wholly owned; nearly 1,080 acres in which the company is a tenant in common with a 90 percent interest; 3,350 acres in tenancy in common with a 50 percent interest; and more than 160 acres in tenancy in common with other fractional interests. Of said total, nearly 7,150 acres are under lease while more than 4,880 acres are unleased. Great Northern Iron Ore Properties is headquartered in St. Paul, Minn.