A 1,000m x 400m gold anomaly was discovered on top of Sona Hill, located 4.8 km southeast of the Toroparu Deposit during regional saprolite geochemical surveys conducted in 2012 & 2013. Subsequent drilling (2015 & 2016) of the top and west flank of the hill over a 1,000m NS x 200m EW (avg). x 160 m deep drilling block has delineated a shallow lode-gold vein mineralized system in the hanging wall above a low angle, west dipping (toward Toroparu) shear zone.
A pit constrained maiden resource estimate including 195,000 oz. Indicated gold resource at an average grade of 1.09 g/t in 5.563 Mt of ore and 241,000 oz. Inferred gold resource at 1.06 g/t in 7.041 MT of ore was defined with analytical data from 12,585 meters of diamond drill cores in 109 deposit specific drill holes completed from 2014-2016.
The Sona Hill deposit is a typical lode-gold vein system hosted by intrusives of intermediate composition which developed in the hanging wall above a low angle, west dipping shear zone (fault) that forms a highly deformed and intensely altered contact zone between the intrusives and an underlying acid volcanic sequence. Gold-Pyrite mineralization occurs mainly within and at the border of tourmaline-feldspar bearing quartz veins, which are surrounded by intense bleaching and alteration halos, both within saprolite and fresh rock types. Mineralization at Sona Hill remains open at depth and along strike.
Sona Hill contains a sizable portion of higher grade mineralization with more than 150,000 oz. Indicated and 189,000 oz. Inferred Resource above 1.5 g/t at 0.7 g/t cut-off grade.
Mineral Resource Sensitivity Table - All Rock Types2
More than 80% of gold mineralization defined to date is contained in rock from 0 to 120m below surface, with 50,000 oz. Indicated gold and 70,000 oz. Inferred gold contained in weathered saprolitic rock. A significant portion of the total saprolite resources is of higher grade, e.g. 38,000 oz. Indicated gold (76% of total in-pit saprolite resource) at a grade of 1.51 g/t above a 0.8 g/t cut-off-grade.
Mineral Resource Sensitivity Table - Fresh Rock & Saprolite
Initial metallurgical test work conducted on Sona Hill saprolite cores indicate 88% leach extraction for gold at a grind of 125 microns and 96% at 75 microns over a 24 to 36-hour leach residence time.