The Kainantu property is located within the New Guinea Thrust Belt, close to its northern contact with the Finisterre Terrane. The property area is underlain by metamorphosed sedimentary rocks of the Early Miocene Bena Bena Formation, unconformably overlain by Miocene age sedimentary and intermediate volcanic rocks of the Omaura and Yaveufa Formations. These formations were intruded in the mid-Miocene by the Akuna Intrusive Complex, which comprised multiple phases of mafic to felsic magma. Late Miocene age Elandora Porphyry dykes formed small high level crowded feldspar porphyry dykes and diatreme breccias.

Mineralization on the property includes gold, silver and copper occurring in epithermal Au telluride veins and Au Cu Ag sulphide veins of Intrusion Related Gold Copper (“IRGC”) affinity and also less explored porphyry Cu Au systems; and alluvial gold. The Irumafimpa-Kora vein deposit is the most advanced project at Kainantu with current defined resources and past modern mining activity in the Irumafimpa area. The deposit occurs in the centre of a large mineralized system approximately 5 km x 5 km in area that has been partly delineated by drilling and comprises several individual zones of IRGC and porphyry style mineralization. The current resources occupy a broad northwest trending mineralized zone more than 2.5 km long and up to 60m wide in which individual veins vary from less than one metre wide that pinch and swell over short distances (Au telluride lodes) to more continuous veins up to several metres wide (Au Cu Ag sulphide lodes).

The Kora veins average 3.1m true width; which is the entire extent of the known veins before cut-off grades are applied. The Mill veins at Irumafimpa average 1.2m true width, which is the entire extent of the known veins before cut-off grades are applied, and also the
minimum width used during resource estimation.

During the mining operation at Irumafimpa between 2006 and 2009, mining was predominantly shrink stoping with some bench (longhole) stoping. The method applied was based on the geological structure and varying vein widths. Multiple independent reviews have shown that previous operators had considerable difficulty with dilution issues during mining which has been mainly attributed to the geological complexity of the veins and a poor understanding of grade distribution within the veins.

The Kainantu processing plant is located approximately 7km from the opening of the 800 portal which accesses the Irumafimpa Mine. Simple processing technology was used to treat Irumafimpa ore. Following crushing, screening and grinding the sulphide bearing material was separated from the nonmineralized host rock by flotation. The design throughput of the plant was 21 tonnes per hour (170,000tpa) and approximately 10% of the ore was recovered as a high-grade gold bearing flotation concentrate with the waste material pumped to an engineered tailings storage facility. The gold bearing concentrate was packed in containers and trucked to Lae from where it was shipped to a smelter/refinery for the recovery of the gold.

Successful commissioning of the Stage 2 Plant Expansion to double throughput capacity to 400,000 tonnes per year and continued development of the twin incline following the lifting of the State of Emergency in June 2020.