THE INSIDE STORY: Blackstone Minerals (ASX: BSX) is progressing the development of the company’s world-class Little Gem cobalt-gold project in the Canadian province of British Columbia.
To say Blackstone Minerals has been busy throughout the month of October would be an understatement as a steady flow of news from the Little Gem project continued to keep market watchers interested as advances emerged.
The company released results from phase two of a completed IP survey at the Jewel copper-gold-cobalt prospect, located 1.1 kilometre north-northeast of the Little Gem prospect.
The Jewel copper-gold-cobalt prospect is associated with the high-grade Jewel underground mine with historic production of 51 tonnes mined between 1938 and 1940.
This production was impressive, returning average mined grades of 73 grams per tonne gold and 0.4 per cent copper with highest grades assayed up to 243g/t gold and 19.2 per cent copper.
These historic grades were supported by Blackstone Minerals’ rock chip samples of up to 98g/t gold, 3.2 per cent copper, 0.1 per cent cobalt.
At over one kilometre long, the recently-defined IP anomalies are much larger and stronger than phase one anomalies Blackstone had previously announced and were interpreted by the company to indicate a large sulphide bearing body associated with the Jewel copper-gold-cobalt prospect.
The new large-scale IP anomalies were also judged to be coincidental with strong geochemical anomalies and favourably located within a major structural setting near the contact between the granodiorite and serpentinite that Blackstone has previously thought as an analogous geological setting to the deposits of the world class Bou-Azzer primary cobalt district in Morocco.
As the Jewel prospect has never been drill tested, Blackstone immediately designated these new, high quality IP anomalies, to be priority drill targets.
“Our field work indicates Jewel is associated with anomalous cobalt mineralisation and with the recent Erebor Cobalt-Gold discovery nearby the Little Gem project is shaping up to be a world class cobalt district,” Blackstone Minerals managing director Scott Williamson said.
“The Petrophysical analysis we completed on core samples from Little Gem indicate the sulphide alteration associated with the cobalt and gold mineralisation at Little Gem has a high IP response.
“These IP/ resistivity surveys have highlighted targets that are consistent with the measured response from Little Gem but significantly larger in size.”
The sulphide ore that was mined at the Jewel mine in the late-1930s was unable to be substantially beneficiated by concentration, resulting in gold values that were not high enough to make a profit by way of direct shipping ore (DSO) to smelters.
Only a small tonnage of ore was extracted at Jewel, after which the claims lapsed and there was no further work conducted at the prospect until Blackstone Minerals acquired its BC cobalt project approximately 12 months ago.
Since acquiring the project, Blackstone has completed an extensive program of prospecting, stream sediment and soil sampling with the geochemical results coinciding and supporting the large-scale IP chargeability and resistivity signatures at Jewel.
The next news to emanate from Blackstone Minerals’ newswire was the receipt of assay results, confirming its Erebor discovery at the Little Gem project.
The results stemmed from surface rock chip samples taken from the Erebor cobalt-gold discovery, located 900 metres along an interpreted ultramafic trend to the south-west of the historic Little Gem adits.
Blackstone claimed the high-grade samples represent the first discovery of substantial cobalt-gold mineralisation in the region since prospectors found similar mineralisation known as Erythrite in the 1930s by identifying a pink cobalt-bloom on weathered mineralisation which led to the discovery of the Little Gem cobalt-gold project.
High-grade cobalt assays from surface rock chip samples taken from the Erebor discovery included:
2.3 per cent cobalt, 32 grams per tonne gold and 1.1 per cent nickel;
1 per cent cobalt;
1 per cent cobalt;
0.6 per cent cobalt;
0.6 per cent cobalt;
0.5 per cent cobalt; and
0.4 per cent cobalt.
High-grade gold and copper assays were also recorded from surface rock chip samples taken from the Erebor discovery, including:
16.7g/t gold and 1.6 per cent copper;
10.4g/t gold; and
1.5 per cent copper.
“These high-grade assays confirm the Erebor discovery as the first known occurrence of high-grade cobalt-gold mineralisation in the region since prospectors identified similar mineralisation in the 1930s, which led to the initial discovery of Little Gem,” Williamson said.
“The Erebor discovery opens up the potential for multiple targets similar to the Bou-Azzer primary cobalt district in Morocco and combined with the recent IP survey results see the Bridge River Mining Camp emerging as a potential world class cobalt belt located in a tier one mining jurisdiction in British Columbia, Canada.”
More news, however, was to emerge from the Jewel prospect in the form of results from further soil sampling that identified major copper-gold-cobalt targets centred on the Jewel prospect.
The new soil anomalies are greater than 1.5 kilometres long and coincide with the earlier IP survey results that indicated a large sulphide bearing body associated with the prospect.
The later surface rock chip samples taken from the Jewel prospect delivered high-grade assay results including:
5.6 per cent copper; and
5.1 per cent copper.
Blackstone signalled these results, combined with its earlier efforts, had made the Jewel prospect the company’s highest priority target to be drill tested at the earliest opportunity.
“Our soil sampling program has identified a major copper-gold-cobalt target at Jewel which coincides with the large IP anomaly we believe to be a substantial sulphide bearing body at depth,” Williamson said.
“We are eagerly anticipating the drilling of these new targets so as to better understand the primary source of the high-grade copper-gold-cobalt mineralisation at Jewel, Little Gem and Erebor.
“We look forward to further results from our 2018 fieldwork program as we continue to unlock what is shaping up to be a potential world class cobalt district.”
Blackstone has already completed an initial six diamond drill holes at Little Gem and at the time of writing was awaiting assay results for the remaining five diamond drill holes.
Drilling to date has intersected the Little Gem structure within metres of the interpreted target.
The 2018 drilling to date has consistently intersected a broad alteration zone, highlighting potential for a major hydrothermal system at Little Gem.
Results from the first six drill holes at Little Gem include:
1.1m at 3 per cent cobalt and 44g/t gold within 4.3m at 1 per cent cobalt and 15g/t gold;
1m at 1.2 per cent cobalt and 5g/t gold within 3.2m at 0.8 per cent cobalt and 4g/t gold;
0.4m at 1.2 per cent copper, 5g/t gold and 0.12 per cent cobalt within 1m at 0.5 per cent copper, 4g/t gold and 0.08 per cent cobalt; and
0.8m at 0.6 per cent cobalt and 9g/t gold within 1.6m at 0.4 per cent cobalt and 5g/t gold.
The carried out by Blackstone since acquiring Little Gem has also led to the discovery of the high-grade Roxey gold-copper prospect.
The Roxey gold-copper prospect is located 1.5km west-southwest of the Little Gem prospect and was visually identified by Blackstone during its due diligence site visit when rock chip samples were taken within the target area which assayed up to 24g/t gold, 1.9 per cent copper and 24g/t silver.
Blackstone Minerals Limited (ASX: BSX)
…The Short Story
Suite 3, Level 3
24 Outram Street
West Perth, WA, 6005
Ph: +61 8 9425 5217
Hamish Halliday, Scott Williamson, Andrew Radonjic, Michael Konnert, Stephen Parsons