Gold Fields

The St Ives mining operations extend from five to 25km south south-west of the town of Kambalda in Western Australia, approximately 630km east of Perth at latitude 31° 12’ S, longitude 121° 40’ E. The nearest major settlement is the town of Kalgoorlie situated 80km to the north, with well-established power grids, access roads and supporting infrastructure.

St Ives controls exploration and mineral rights over a total area of 112,092ha, which is the total of the managed granted tenements and has security of tenure for all current exploration and mining leases that contribute to future Mineral Reserves (two additional tenements (291ha) are non-managed).

St Ives currently operates one underground mine, which is accessed via a decline, and three open pits, a centralised administrative office, an engineering workshop and a 4.7Mtpa CIP processing plant.

St Ives is situated in an area of arid bush land. While occasional storm activity may cause minor delays to open pit mining operations, the climatic conditions do not materially impact on the normal operations of the site.

St Ives lies within the Kambalda domain, a subset of the Norseman- Wiluna Belt. The Kambalda domain is bound by the north-northwest trending Boulder-Lefroy fault (BLF) and Zuleika shear. The region has undergone four compressional events predated by early extension and has been metamorphosed to upper greenschist or lower amphibolite facies.

The main structural feature of the St Ives area is the gently south-plunging Kambalda anticline, which extends 35km from the south end of the Kambalda dome to the Junction mine. The majority of known gold deposits are proximal to the trace of the anticlinal axis. A major second order structure known as the Playa shear splays off the BLF shear zone and can be traced through the St Ives field for a distance in excess of 10km.

There are several styles of gold mineralisation at St Ives. Individual deposits may contain more than one of these styles:

• Lode mineralisation: Archaean lode mineralisation typically consisting of 0.5m to 20m-wide mesothermal vein complexes that may also have hydraulic breccias and/or mylonites
• Supergene mineralisation: Broad zones of flat-lying gold mineralisation in weathered Archaean and overlying tertiary sediments
• Palaeoplacer mineralisation: Placer deposits hosted by palaeochannels in the unconsolidated tertiary sediments that overlie the Archaean basement

Archaean orogenic greenstone gold hosted in a number of different styles of mineralisation. Lode, supergene and palaeoplacer-style deposits characterise the range of ore body types.

Ongoing extensional and brownfields exploration continues and could increase the LoM given the prevailing Inferred Resource and strengthening exploration pipeline. It is estimated that the current known Mineral Reserves will be depleted in 2021 (four years).