THE DRILL SERGEANT: Bulk minerals explorer Sheffield Resources has received results from a 31 hole drilling program at its Irwin heavy mineral sand (HMS) project located 80 kilometres southeast of the port of Geraldton in the Mid West region of Western Australia.
Sheffield said the latest drill results from Irwin, combined with results of drilling carried out by North Mining in 1994 to confirm the presence of a large 1.5 kilometre to 2.5 kilometre wide zone of low grade dunal-style mineralisation.
The company has also increased the strike length of the zone to 5km.
Noteworthy drilling results from the drilling include:
– 18.0 metres at 1.25 per cent heavy mineral from 6.0 metres;
– 13.5m at 1.40% HM from 7.5m;
– 15.0m at 1.66% HM from 4.5m;
– 12.0m at 1.70% HM from 7.5m; and
– 9.0m at 2.58% HM from 25.5m.
Sheffield Resources managing director Bruce McQuitty said the drill results outlined a large open-ended dunal mineral sands system in an area that has received little previous exploration.
“The Irwin project represents a large virgin exploration target, strategically located close to infrastructure and adjacent to Tiwest’s Dongara deposit,” McQuitty said in the company’s announcement to the Australian Securities Exchange.
“It is one of several projects that Sheffield is advancing in the world class North Perth Basin mineral sands province.”
Mineralisation identified by the latest drilling campaign averages 10m in thickness but is locally up to 18m thick at 1% HM cut-off.
It is variably overlain and enveloped by a halo of lower grade (0.5-1% HM) mineralisation.
Sheffield indicated that an important feature of the dunal mineralisation is the low slimes content (weighted average 6.4%) and low oversize (3.0%), which favour low cost processing techniques.
The Irwin project is situated 60km north of Eneabba in what Sheffield describes as a, “highly prospective setting on the Swan Coastal Plain at the foot of the Gingin Scarp”.
Sheffield recently applied for an additional Exploration Licence (ELA70/4189) which extends the Irwin exploration target for an additional 10km to the north.
The results follow the company’s announcement last month of its maiden resource at its nearby Yandanooka project of 1.84 million tonnes of contained heavy mineral within a total resource of 71.75 million tonnes at 2.6 per cent heavy mineral, comprising 61 million tonnes at 2.8 per cent heavy mineral (Indicated) and 10.75 million tonnes at 1.1 per cent heavy mineral (Inferred).