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Deposit Synonyms
EML 6366; ML 6314; ML 6442; RL 103
Mineral District
Deposit Summary
coarse grained, specular hematite of hydrothermal replacement origin in host granitoid of the Mount Woods Complex. Resource ~20Mt @ 63.7%Fe to 120m depth. Active mine to end 2014 for recovery ~7mtonne at 62%Fe.
Deposit Description
PECULIAR KNOB, a deposit of 2 NE-trending sub-parallel, elongate lenses of coarse grained, specular hematite in host granitoid of the Mount Woods Complex. Both lodes pinch and swell along strike, both dip steeply to NW. There are minor offsets of the lodes by cross faults. Along strike the lenses taper down to narrow veins. It was initially identified by its prominent linear aeromagnetic signature. Follow up drilling identified hematite bodies with overall dimensions ~1 km long EW, by ~35m wide. The deepest drill intersection indicated massive hematite to >300m depth. Although the mineralogy is dominantly non-magnetic hematite, it was discovered that the strong magnetic signature was due to strong remnant magnetisation attributed to a preserved magnetite core within individual hematite grains.
Younger cover sediment is a thin layer of Quaternary, red-brown clay, sand and silt over 12-20m of flat-lying mudstone of the Cretaceous Bulldog Shale containing minor gypsum.
The hematite deposit was thought to be of hydrothermal origin, formed by the replacement by hematite of a favourable host rock constituted dominantly of quartz and magnetite. Later drilling by Western Plains Resources LTD to a depth ~120m identified a JORC-compliant resource of 19.4Mt @ 63.7% Fe, 0.01% P, 7.3% SiO2, 0.3% Al2O3, and 0.5% LOI, using a cut-off grade of 55% Fe (2010). Purchased by Southern Iron who commenced mining in 2012 to recover >8Mtonne at ~62%Fe to June 2015 before the mine was closed due to falling commodity prices.
Discovery Year
? 1985
Commodities
Iron, Rare Earths
Ore Minerals
Hematite
Gangue Minerals
Quartz
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