Aldiss deposits Main Zone, Harry’s Hill, Tank/Atreides, Italia/Argonaut, French Kiss and Spice are hosted in amphibolites and metasediments striking north/south and dipping steeply to the west. The vast majority of the gold mineralisation occurs in amphibolite rock that has metamorphic foliations generally running subparallel to the sedimentary layering. The gold mineralisation dips steeply to the west with a variety of plunges from 30° to the north at the Karonie main zone deposit to 30° south at French Kiss.

Main Zone, Harry’s Hill, Tank/Atreides and Spice deposits are amphibolite grade metamorphosed. Italia/Argonaut and French Kiss are greenschist grade metamorphosed.

Open pit mining will be focused at Karonie South through FY21. Material movements and strip ratio are higher in first half, prior to the strip ratio declining to below the life of mine average and grades increasing to above the life of mine average in the second half. Silver Lake has a strong pipeline of projects at Aldiss with the potential to continue mining operations beyond Karonie South. The most advanced project is Tank South, where Silver Lake is currently evaluating the optimal mine plan. Silver Lake is also evaluating a potential open pit development at both Tank and Atreides.

All ore from the Mount Monger Operation is processed through the 1.3 mtpa Randalls facility, located 65 km south east of Kalgoorlie and is 15 km from the Daisy Complex.

Gold recovery consists of both a gravity circuit containing two gravity concentrators an intensive cyanidation unit and hybrid CIP circuit comprising two leach tanks and six adsorption vessels. Gold is stripped from the loaded using a pressure Zadra type elution circuit consisting of two elution columns and the gold is subsequently recovered from the cathodes of the gravity and electrowinning cells.