Blackstone Minerals (ASX: BSX) has revealed the first assays from three maiden drill holes at the Ban Chang prospect within the Ta Khoa nickel sulphide district in Vietnam, confirming significant high-grade results.
The best result came from drill hole BC20-01, which intersected 1.5m at 2.2% nickel, 2.12% copper, 0.13% cobalt and 2.66 grams per tonne of platinum group elements (PGE), including 1.05m at 2.98% nickel, 1.22% copper, 0.18% cobalt and 3.43g/t PGE.
The maiden drill holes were part of Blackstone’s testing of high-priority electromagnetic targets generated from 25 massive sulphide vein prospects throughout the Ta Khoa district to supplement the potential bulk open pit mining scenario at the Ban Phuc prospect and the King Cobra discovery zone, where drilling continues at depth.
The company started drilling at Ban Chang in late May with today’s news following announcements made earlier in June that massive sulphide nickel was identified over 1km of strike, including intersecting a 9.15m thick zone of sulphide vein mineralisation.
Ban Chang’s high-grade feed potential
According to Blackstone managing director Scott Williamson, Ban Chang is a key prospect that has potential to add high-grade feed to a bulk open pit mining scenario at Ban Phuc.
“Our first assays from Ban Chang confirm a high-grade magmatic nickel sulphide vein with significant by-products including copper, cobalt, platinum and palladium,” he said.
“When the by-products are included, the overall grades of the massive sulphides from Ban Chang are substantially higher than those successfully mined from the Ban Phuc massive sulphide mine during lower nickel prices,” Mr Williamson added.
Drilling is part of Blackstone’s aim to build its resource inventory at Ta Khoa to supplement the Ban Phuc maiden resource, which is on track for completion in the third quarter of 2020.
The company said a second drill rig will continue to follow the in-house geophysics team throughout the Ta Khoa district, testing other prospects including King Snake, Ban Khoa, Ban Khang and further targets at Ban Chang.
Also due in the third quarter is Blackstone’s scoping study on downstream processing to produce nickel sulphate for the lithium-ion battery industry.
This study is expected to provide details for joint venture partners to formalise the next stage of investment.
The Ta Khoa project in northern Vietnam including an existing modern nickel mine and a 450,000 tonne-per-annum processing plant. The operation has been under care and maintenance since 2016 due to falling nickel prices.