THE CONFERENCE CALLER: It’s seems one of the mantras underpinning Musgrave Mineral’s (ASX: MGV) gold exploration strategy in Western Australia is an old, but simple, one – grade is king. By Mark Fraser
From all indications this chant is quietly being repeated by the company as it goes about sizing up high margin gold ounces at its Cue project in WA’s Mid West.
Located 40 kilometres north of Mt Magnet just off the road to the historic mining town of Cue, the undertaking – via the advanced Break of Day ore body – already has an indicated and inferred resource of 686,000 tonnes grading 7.2 grams/t gold for 199,000 oz along 28 km of strike.
At the moment, though, Musgrave Minerals is focusing on the establishment of new resources at its recent Starlight and White Light discoveries, a task it hopes to complete by the end of this month.
These targets – which effectively revealed Cue’s robust upside to the market – have provided “a significant change for Musgrave” by exposing some high angle, close-to-surface mineralisation in previously undiscovered north-east lodes to the south.
During his presentation at the Diggers & Dealers Mining Forum in Kalgoorlie-Boulder, the company’s managing director Rob Waugh pointed out that in the past around 3-4 metres of hardpan cover over had more or less disguised potential mineralisation.
“And as far as surface geochemistry goes, we are in an area where there has been a fair bit of historical activity around small, little pits and historical operations back from 1885, so a long way back,” he noted.
“But that has led to a significant geochemical halo in this region, which has meant that people haven’t been able to focus on individual lode orientations very well through geochemistry.
“So, there is definitely opportunity here going forward (for) making new discoveries.
“It’s important to note that when we turned the rig around here, about six months ago, this is the first time anyone has drilled in this whole belt in this orientation – effectively forever.
“First drilling here was in the 1970s, but no one has turned the rig around.”
Some of the high-grade gold intersections at Starlight so far:
22m at 21 g rams per tonne gold (from 2m);
14m at 190g/t (4m);
77m at 13.3g/t (7m);
68m at 5.9g/t (21m);
31m at 44.8g/t (37m);
12m at 109g/t (40m);
42m at 6.8g/t (70m), and;
60m at 13.1g/t (77m).
Meanwhile, new mouth-watering gold intercepts under 2-3m of hardpan cover where there had been no previous drilling included 5m at 13.4g/t (28m) and 4m at 15.4g/t (41m).
In addition, Waugh said, gold recoveries achieved from metallurgical test work at Break of Day and Lena (to the north-west) totalled 96-97 per cent from conventional gravity and carbon-in-leach processing.
Furthermore, high gravity recoveries (over 73%) were also made in the fresh rock.
This, he noted, was good when compared to typical Yilgarn Craton gold ores and suggested low reagent use and reduced processing costs. Importantly, there were no deleterious elements present.
As part of its ongoing exploration strategy, Waugh explained, Musgrave Minerals would continuing step out drilling in a north-east orientation.
“Some of these grades we are seeing are the highest intersected in Australia and the world in the last 12 months, and the fact we are getting them within three to four metres of surface is phenomenal,” he told the Diggers & Dealers crowd.
“People have been talking about not being able to find high grade surface mineralisation in Australia, and obviously we are an exception to that.”
Ultimately, Waugh said, Musgrave Minerals was looking for high margin oz.
“The focus is for us is not on tonnes, it’s not on oz, but on margins,” he noted.
“For us really it is about grade.”