Corinthia Underground

/Corinthia Underground
Corinthia Underground 2019-04-16T06:58:24+00:00

LOCATION

Corinthia is located 15 kilometres north of the Western Australian wheatbelt town of Southern Cross (370km east of Perth).

Since the discovery of gold at Corinthia in the early 1900’s, a total of 2.7MT @ 3.4 g/t has been mined for 300koz produced. This includes 75k ounces at 5.7g/t from underground, including recent mining by Adaman.

Adaman acquired the project in 2017 and following a period of drilling and evaluation commenced mining in 2018.

STATUS

Not withstanding its high-grade production history Corinthia remains poorly explored along its 1.2-kilometre strike with only shallow drilling (to 150 meters) and mining (to 90 meters, in the northern end).  Adaman has committed to an exploration decline / bulk sample evaluate the deposit adjacent to and below the existing underground workings, however sees enormous potential to grow resources and production profile beyond this first Stage and is progressing plans to evaluate and build a long term, sustainable underground and open pit production centre.

Corinthia ore is currently being toll treated, however, Adaman has recently acquired an option to purchase the Burbanks facility in Coolgardie with plans to upgrade to accommodate Corinthia and satellite ores.

GEOLOGY & MINERALISATION

The Corinthia deposit is situated in the Southern Cross Province of the Archaean Yilgarn Craton. It lies on the eastern margin of the Southern Cross greenstone belt that extends along strike for 300km from Mt. Jackson in the north to Hatter Hill in the south.

The province has a long history of gold production and hosts several +1 million-ounce deposits such as Bounty, Yilgarn Star, Marvel Loch, and Copperhead.

Regionally, the belt is a strongly deformed, metamorphosed synformal greenstone composed of a lower unit of quartz-muscovite schist (probably foliated granite) overlain by series of mafic and ultramafic volcanics and sedimentary sequences. Most of the belt’s production has been derived from shear-hosted deposits (such as Marvel Loch, Yilgarn Star and Frasers) and to a lesser extent fold hinge deposits, usually in BIF (such as Copperhead, Golden Pig and Bounty).

The mine sequence at Corinthia from east to west comprises sericite-muscovite schist, Banded Iron Formation, interlayered and sheared ultramafic (hosting the main quartz lode) and mafic amphibolites.  Late lamprohyre dykes and sills are common within the ultramafic.

Mineralisation has been defined over a strike length of 1.2 kilometres and to a depth of approximately 200 meters. The main quartz lode is continuous along the entire strike length and up to 10 meters in width. Subordinate mineralisation is hosted within the isoclinally folded Banded Iron Formation and within foliation parallel quartz shears within the hangingwall ultramafic/mafics.

The main quartz-dominant lode occurs proximal to the eastern ultramafic/Banded Iron Formation contact and although reasonably tabular in geometry it appears to have undergone multiple deformational events.  Mineralisation is associated with pyrite-pyrrhotite (+/- cpy) which can occur as disseminations and layers within contact parallel shearing, or as irregular (in terms of geometry and dimensions) massive sulphide matrix of crackle breccias with associated veinlet networks. Gold also has a strong associate with the bismuth alloy maldonite. Post mineralisation shearing and intrusion of lamprophyre sills has resulted in zones of offset and horse-tailing of the vein.

In conjunction with the current underground bulk sample, resource development drilling is planned targeting resource upgrades to support an initial 80k ounce p.a. operation. Longer term, the aim is to define a +1-million-ounce mineral resource and 0.5 million ounce ore reserve sufficient to support a +1 million tonne p.a. bulk underground mine, stand-alone processing facility and +115k ounce p.a. production profile.