Thor Mining PLC (AIM:THR, OTC:THORF, ASX:THR) has said the latest drilling results are encouraging from the Kelly's prospect, part of its Ragged Range project in the Pilbara, Western Australia.
The best intercepts included 8 metres (m) at 1.31% copper and 0.1 grammes a tonne (g/t) gold from a depth of 4m, including 3m at 2.9% copper and 0.17 g/t gold; 1m at 0.91 g/t gold; and 4m at 0.1 g/t gold, 0.3% copper, 0.9% lead and 0.2% zinc.
However, the AIM-traded company also had to announce a correction to drilling results released on November 4 due to an error made at a laboratory in Kalgoorlie.
READ: Thor Mining hits high-grade gold at Kelly's Ridge
The 12.2 g/t gold sample was an erroneous result based on the laboratory making a sample swap with an internal standard, Thor said, adding that the assay has subsequently been reported at less than 0.01 g/t gold.
"Disappointingly, due to a testing error at the Bureau Veritas laboratory, the high-grade gold result announced in November was erroneous,” said Thor’s managing director Nicole Galloway Warland in a statement. “Thor is undertaking an investigation into the laboratory error to ensure that the highest standard of procedure and reporting is provided going forward."
“These latest drill results are encouraging; however, further work is required to fully explain why the high-grade gold and copper in surface rock chips is not repeated in very shallow drill intersections," she added.
Drilling at the Kelly's prospect was designed to test below the high-grade rock chips. Previous rock chip sampling at surface reported up to 15 g/t gold and 535 g/t silver along the 1 kilometre Kelly’s ridge.
Bureau Veritas is a multinational group with more than 200 laboratories worldwide.