McCalls is located 110km to the North of Perth near the town of Gingin in Western Australia. It is proximal to the Brand Highway and Moora to Bindoon road, as well as rail which links the ports of Geraldton to the north and Kwinana/ Fremantle to the south. The Resource is on tenements E70/3929, E70/3967 and E70/4922.
Historic exploration in the early 1990’s by BHP outlined a large, low grade (1.0 -1.5% HM) heavy mineral sand deposit covering an area of 30km2 at McCalls, extending from near-surface to depths of typically 50m. Further drilling by Sheffield shows the mineralisation has an average thickness of 33m, with an average overburden thickness of 6m (see Mineral Resource and Ore Reserve Statement, ASX release 03 October 2018).
On 01 October 2018 the McCalls prospect Mineral Resource estimate was updated to include historic drilling from the recently granted Exploration License E70/4922, which adjoins the current Mineral Resource area. It also excluded a high slimes portion surrendered by Sheffield. McCalls (at a 1.1% HM cut-off) has a Mineral Resource of 3.6Bt @ 1.3% HM, with an indicated component of 1.63Bt @ 1.4% HM, and an inferred component of 1.98Bt @ 1.2% HM.
Contained valuable heavy mineral (VHM) at McCalls totals 43,290kt composed of 37,730kt of ilmenite, 2,430kt of zircon, 1,700kt of rutile and 1,430kt of leucoxene. This includes an indicated 20,570kt of contained VHM comprising of 17,940kt of ilmenite, 1,210kt of zircon, 770kt of rutile and 650kt of leucoxene, and an inferred 22,720kt of contained VHM comprising of 19,790kt of ilmenite, 1,220kt of zircon, 930kt of rutile and 790kt of leucoxene (see Mineral Resource and Ore Reserve Statement, ASX release 03 October 2018).
The McCalls deposit covers an area of up to 14km east-west and up to 12km north-south. Mineralisation occurs from surface to depths of up to 96m, with an average thickness of 28m.