Strongbow Exploration makes high-grade copper-tin discovery
Strongbow Exploration Inc. [SBW-TSXV; SBWFF-OTC] reported the discovery of a new zone of high-grade copper-tin mineralization located between the historic United Mine and Consolidated Mines at its United Downs exploration project, Cornwall, southwestern United Kingdom. The discovery was made in drill hole GWDD-002, drilled by Cornish Lithium. Cornish Lithium has the right to explore Strongbow’s mineral rights in Cornwall for lithium in brine occurrences while Strongbow retains the rights to any hard rock mineralization.
HIGHLIGHTS
• Diamond drill hole GWDD-002 was drilled by Cornish Lithium to test the potential for lithium in brine at United Downs, within the historic Gwennap copper and tin mining district;
• Gwennap was the richest copper producing region in Cornwall (and the world) in the 18th and early 19th centuries, and at that time was referred to as “the richest square mile on earth”;
• GWDD-002 intersected semi-massive sulphide mineralization between 90.60 and 105.29 metres downhole depth;
• Assays returned 14.69 metres grading 7.46% copper, 1.19% tin, and 0.15% zinc from 90.60 to 105.29 metres downhole length;
• Further drilling is required to confirm true width, as well as the strike and dip of the mineralized zone;
• Three individual sample intervals returned assays greater than 20% copper – final results for these overlimit assays are pending, and will be reported when received;
• The semi-massive sulphide mineralisation is similar in style to that mined at Wheal Jane and Mount Wellington mines, located 1.5 km along strike to the east; and
• Copper grades reflect recorded historical mine production from United Mines located approximately 200 metres to the south.
BACKGROUND
Strongbow completed the acquisition of the South Crofty tin project plus additional mineral rights located in Cornwall, UK, in July 2016. The additional mineral rights cover an area of approximately 15,000 hectares and are scattered throughout Cornwall. Some of these mineral rights cover old mines that were historically worked for copper, tin, zinc, and tungsten.
In January 2017, the company entered into an agreement with Cornish Lithium, a private exploration company, whereby Cornish Lithium was granted the right to explore Strongbow’s mineral rights in Cornwall for lithium in brine occurrences.
In 2019 Cornish Lithium provided notice of its intention to conduct diamond drill testing for lithium in brine on Strongbow’s United Downs mineral rights. United Downs is located approximately 8 km east of South Crofty and lies within a densely mined district, historically referred to as Gwennap. Two diamond drill holes have been completed, for a total length of 1,858 metres. Strongbow is logging and sampling the remaining drill core from both GWDD-001 and GWDD-002, and is applying for a drill permit to drill test the strike extension of the lode structure intersected in GWDD-002.
UNITED DOWNS PROJECT
The United Downs Project covers, or is located immediately adjacent to, four former copper and tin producing mines: Consolidated Mines and United Mines to the west; and, Mount Wellington and Wheal Jane Mines to the east.
At the nearby South Crofty Mine, copper-tin-zinc-tungsten mineralization hosted within the killas passes into tin mineralization at depth as the mineralised vein-like structures pass into the underlying granitic host rock. The same zonation potentially exists at United Downs, where only the killas-hosted mineralization has been exploited to date. The underlying granite, which is a target for further tin mineralization, was encountered in GWDD-002 between 300 and 600 metres and again at a 700-metre vertical depth.
The nearby Wheal Jane mine was discovered and developed into a modern mine in the late 1960s, initially by Consolidated Goldfields, and thereafter by Rio Tinto Zinc. Mining activities at Wheal Jane ceased in early 1991, due largely to the Tin Crisis of 1985, but processing of South Crofty ore continued until March 1998 when ongoing low tin prices forced its eventual closure.