Mineral Point is a village in Washington County, Missouri, United States. The population was 351 at the 2010 census. Mineral Point had its start in the 1850s as a lead-mining settlement. The community owes its name to the wealth of minerals found in the vicinity. Mineral Point was situated along the St. Louis, Iron Mountain and Southern Railway. A post offic…Mineral Point is a village in Washington County, Missouri, United States. The population was 351 at the 2010 census. Mineral Point had its start in the 1850s as a lead-mining settlement. The community owes its name to the wealth of minerals found in the vicinity. Mineral Point was situated along the St. Louis, Iron Mountain and Southern Railway. A post office has been in operation at Mineral Point since 1858.