At Sunrise Dam, gold mineralisation is structurally controlled and vein hosted. The style of mineralisation can be differentiated depending on the structure or environment in which it is hosted. There are three dominant styles recognised:

• shear-related and high strain, e.g. Sunrise Shear Zone

• stockwork development in planar faults with brittle characteristics (these occur in all rock types and are commonly concentrated at contacts within the volcanic stratigraphy or the porphyry margin and within hinge positions within the magnetite shales) e.g. Western Shear Zone, Watu, Cosmo, Summercloud

• placer-style mineralisation hosted within the fluvial sediments

Mineralisation is typically hosted in quartz carbonate veins and breccias with varying quantities of pyrite and arsenopyrite. Gold occurs as free gold and is also occulded in the sulphides. The gold mineralisation is often associated with strongly altered country rocks proximal to the shear and fracture network that the hydrothermal fluids have passed through.

Open pit production began in 1997 and has now been completed at a final depth of 500m below surface. Underground mining commenced in 2003 with a number of different mining methods being applied, depending on the style of mineralisation and grade of the geological domain.

Mining is carried out by contractors. The primary mining method is bulk mechanised sub-level open stoping using stabilising pillars and waste back fill where possible.

The owner-managed processing plant comprises conventional gravity and carbonin-leach (CIL) circuits, with a flotation and fine grind circuit commissioned in mid-2018 to improve metallurgical recovery.