The Cadia East deposit occupies a mineralized zone 2.5 km in strike length, 600 m in width and over 1,900 m in vertical extent. It is located below and to the east of the Cadia Hill orebody.

At Cadia East, sheeted quartz-calcite-bornite-chalcopyrite ± molybdenite veins, oriented sub-parallel to E-SE trending monzonite intrusions define a high grade resource at depth (Wilson, 2003). Pervasive biotite-orthoclase-albite-magnetite ± actinolite alteration envelopes surround these veins forming a zone of calc-potassic alteration. Propylitic (epidote-magnetite-hematite-chlorite) alteration extends laterally away from this calc-potassic core (Wilson, 2003). Distinctive hematite dusting of hydrothermal feldspars occurs throughout the propylitic alteration at Cadia East, a characteristic feature of many alkalic porphyry Au-Cu deposits (Holliday and Cooke, 2007).

The Cadia East mineralization consists of a package of steeply dipping, sheeted quartz veins forming a near vertical slab with dimensions approximately 2.5 km long, greater than 1.6 km deep and at least 200 m to 300 m wide. A high grade gold core is found at depth towards the eastern end of this vein package. Smaller pods of higher grade material are located above and lateral to the high-grade core.

Mineralization at Cadia East can be divided into two broad overlapping zones: an upper, copper rich disseminated zone and a deeper gold-rich zone associated with sheeted veins. The upper zone forms a relatively small cap to the overall mineralized envelope and has a core of disseminated chalcopyrite (and rare bornite), capped by chalcopyrite-pyrite mineralization (Fox et al., 2009).

The upper zone mineralization is stratigraphically controlled within the volcaniclastic unit. This zone is transitional to the deeper vein style mineralization. The deeper zone is localized around a core of steeply dipping sheeted quartz-calcite-bornite-chalcopyritemolybdenite, with the highest gold grades associated with the bornite-bearing veins. Copper and molybdenite form a mineralized blanket above and to the east of the higher grade gold envelope.

Cadia East deposit is a large underground mining operation using the panel caving method (Cadia East Project). The deposit is mined in a number of lifts each comprising multiple panels.

Ore mined from the Cadia Valley deposits is treated in two operating process plants producing gold rich copper sulphide flotation concentrate for export, and gravity gold doré.