Sioux Jasper is restricted to the lower conglomerate of the Sioux Formation of southwestern Minnesota and southeastern South Dakota. Primary sources occur at Sioux Falls. Other outcroppings occur in Cottonwood County, Minnesota, Buena Vista County, Iowa and into Nebraska. Occurs from northwestern Iowa to southern South Dakota and southwestern Minnesota. Occurs in both bedrock and glacial tills. Reported as glacial till in Richardson County, Nebraska. Occurs at Sioux Falls, South Dakota.
