Stonehorse Energy Ltd, formerly Nickelore Ltd, is an Australia-based company that operates through its subsidiary, Lone Star Energy Limited (Lone Star). Lone Star is an oil and gas exploration and development company. It has working interests in two oil and gas projects: Greever Prospect and Burgess Prospect. It has approximately 25% working interest in the Greever Prospect, which is located in the Pan Petro Field in the eastern edge of Hansford County, West Texas. It has approximately 98% working interest in the Burgess Prospect, which is located in the Southwest Fort Supply field in the north-eastern corner of Ellis County, in Oklahoma.