The Runruno deposit is located at the intersection of the margins of two district-scale calderas, major NE and NW fault lines and several late, small volume, composite volcanic centres.

Significant local uplift, intensive alteration and mineralisation demonstrate the presence of a large gold system with the geological potential to provide a significant resource of both gold and molybdenum.

Evidence from previous studies indicate the potential for significant further exploration beyond the exiting Runruno resource area. Evidence has been amassed via drilling, test pit Au+Mo+As anomalies and PDX sampling and mapping. This was supported further in March 2008 following a site visit by Dr Eric Jensen, an expert on alkaline intrusive gold mineralisation, where the potential for further mineralisation within the immediate area was highlighted.

Exploration currently focuses on a volcanic centre measuring ~3km in diameter. Geological features in this area include a syentic-monzonite intruded into a coeval trachytic, volcanoclastic and tuffaceous volcanics. The area is extensively argillised and argillic with alteration caps N to NE and trending zones of intense sulphide-phyllic alteration around the western and southern rim of the centre. Linear phyllic zones are exposed over a 1000-m x 200-m area within the argillic alteration at Cobocbocan Creek (~750-m ASL.) A broad (2600-m X 800-m) E – W moderate phyllic zone is located on the northern margin of the volcanic centre. The argillic cap is present from ~750-m ASL to the Cobocbocan Peak (970-m ASL.) Mineralisation appears constrained between 500-m to 750-m ASL.

Past sampling and drilling have established economic grade intercepts within these intense phyllic zones and further exploration and evaluation has demonstrated large untested extensions to the E and SE that may continue under and be obscured by the argillic alteration cap.

Traditional excavator and truck approach, with drill and blast.

Mining operations:

- Surface cut and fill:
- Initial pit is created which is then back filled as mining progresses;
- Continuous rehabilitation integrated;

- Ore mined at 2.1Mtpa to 1.6Mtpa over remaining LOM;

- Total mine movement of 11.3Mtpa to 6.8Mtpa over remaining LOM;

- Komatsu mining fleet – 100t haul trucks, 2 excavators, 2 bulldozers and ancillary fleet;

- Small ancillary and construction fleet contractor;

- Waste from the pit also used as mass fill in the construction of the RSI;

- Overflow surface waste dumps well established.

Pit design:
- Open pit area – 600m x 1,500m – multiple stages;
- Staged pit which mines longitudinally along the ore body to provide smooth the strip ratio and ore delivery to the plant;
- Rate of vertical versus horizontal advance is the key criteria in developing the schedule and pit design;
- Progressive backfilling of the pit void enables the highest environmental performance.

During FY 2019 overall gold recovery from processing operations was 70.8% which is significantly below the feasibility forecast of 91% but well above 2018 levels of 57.9%.

The process plant uses conventional crushing, grinding, gravity, flotation, and carbon-in-leach processes along with BIOX® technology to produce gold ore bars.

The mine uses the proven BIOX® process for the pretreatment of refractory concentrate ahead of a conventional carbon-in-leach (CIL) processes to recover gold and the ASTER™ process for the detoxification of the CIL residue prior to discharge to the Residue Storage Impoundment (RSI).

BIOX was selected as the preferred technology based on the lower capital and operating cost of the process combined with the ASTER process for treatment of the CIL residue prior to discharge to the TSF. BIOX and ASTER commissioning was completed in 2016 with the first BIOX product pumped to the CIL section.

The Runruno BIOX® circuit is d ........