Assays of drill hole GWDD-002, drilled by Cornish Lithium, returned 14.7m of core grading nearly 7.5% Cu and 1.2% Sn. Cornish Lithium has the right to explore Strongbow‘s mineral rights for lithium brine concentrations. However, Strongbow retains the rights to hard rock mineralisation.
Despite the positive results, the mineralised vein has not been fully defined. The company notes that further drilling will be required to confirm its true width, strike and dip. This will help orient the vein in relation to other mineralisation in the area, and reveal further exploration targets. One such target is the underlying granite. The current drill hole sampled mineralisation in the overlying rock (killas), whereas at South Crofty, the granite hosts much of the tin. According to Strongbow, “The same zonation potentially exists at United Downs, where only the killas-hosted mineralisation has been exploited to date”.
When Strongbow acquired South Crofty in July 2016, it also received additional mineral rights. These rights cover ~15,000 hectares across Cornwall, and include the United Downs area. The United Downs project covers four former copper and tin mines: Consolidated Mines, United Mines, Mount Wellington, and Wheal Jane. Rio Tinto Zinc operated Wheal Jane until early 1991, but closed the mine due to low tin prices following the Tin Crisis of 1985. Processing of ore, which originated from South Crofty, continued until 1998.