A targeted exploration program by Blackstone Minerals (ASX: BSX) has identified new massive sulphide vein, semi-massive sulphide vein and net-textured sulphide opportunities within the Ta Khoa district in Vietnam.
Drilling at the Suoi Phang prospect intersected 2.95m of sulphides using portable xray fluorescence (pXRF) readings indicating the presence of up to 20% nickel.
The prospect is located at the far western end of the Ta Khoa licence area and is hosted within the Devonian metasediments of the Ban Mong Formation.
Massive sulphide was exposed in a historical adit and two gossans were exposed in historical trenching (with assays up to 5.9% nickel).
The northern gossan measures 120m in strike length and the south part of the gossan is 100m long.
Blackstone’s exploration at Suoi Phang is following up targets generated from surface electromagnetic surveying.
Suoi Chanh results
At the Suoi Chanh prospect, a second drill hole intersected semi-massive sulphides consistent with Blackstone’s EM targeting.
Suoi Chanh is located at the eastern end of Ta Khoa and characterised by a high density of mafic-to-ultramafic dykes which suggest the existence of magma sulphide zones.
One of the holes at this prospect intersected a mafic-ultramafic dyke of 2.55m thickness with 0.1m semi-massive sulphide.
It is believed to indicate the potential to find massive sulphide veins common within the Ta Khoa district.
Blackstone managing director Scott Williamson said the new opportunities would benefit the company’s presence in the Ta Khoa district.
“This is an exciting phase of exploration as we start to look at massive sulphide opportunities in addition to our established resources at Ban Chang and King Snake,” he said.
“Suoi Chanh is an example of our in-house geophysics team’s proven track record, with success being achieved from the second drill hole [and] we look forward to continuing to systematically assess the massive sulphide potential of this area.”
Mr Williamson said the company continues to drill its the advanced Ban Chang and King Snake deposits, primarily focusing on upgrading current resources into a higher confidence category.
Highlights from recent infill drilling at Ban Chang were 9.6m at 2.02% nickel, 1.92% copper, 0.1% cobalt and 3.04 grams per tonne platinum group elements (PGE) from 60.1m, including 4.8m at 3.38% nickel, 3.07% copper, 0.16% cobalt and 5.29g/t PGE from 63.7m; 6.75m at 1.44% nickel, 2.1% copper, 0.08% cobalt and 1.32g/t PGE from 27.7m, including 3.65m at 2.58% nickel, 2.1% copper, 0.15% cobalt and 1.21g/t PGE from 30.8m; and 25.55m at 0.63% nickel, 0.43% copper, 0.04% cobalt and 0.33g/t PGE from 43.65m, including 3.57m at 2.17% nickel, 0.82% copper, 0.12% cobalt and 0.94g/t PGE from 62.43m.
Recent drilling at King Snake indicated potential for the deposit to continue to plunge further west and at depth.
Best assays were 15.7m at 1.25% nickel, 0.69% copper, 0.05% cobalt and 1.66g/t PGE from 249.5m, including 6.02m at 2.18% nickel, 0.62% copper, 0.08% cobalt and 2.97g/t PGE from 250.4m; 1.92m at 3.02% nickel, 0.63% copper, 0.11% cobalt and 2.13g/t PGE from 400.5m; 1.35m at 3.67% nickel, 0.54% copper, 0.15% cobalt and 2.25g/t PGE from 154.1m; and 2.52m at 1.07% nickel, 0.35% copper, 0.04% cobalt and 1.93g/t PGE from 321.3m.