Doebrich and Theodore (1996), Theodore (1998), and Theodore (2000) described the deposits at Marigold as distal disseminated silver–gold deposits. These deposits are disseminated equivalents of polymetallic vein deposits, characterised by a geochemical signature that includes silver, gold, lead, manganese, zinc, copper, antimony, arsenic, mercury, and tellurium (Cox and Singer, 1990). Typically, they contain substantially more silver relative to gold than other types of disseminated gold deposits and may feature supergene enrichment of silver if significantly oxidised.

Gold at Marigold is currently mined from multiple deposits located on a 10 km by 1.5 km area. From north to south, historical and future mineral deposits at Marigold include 32 North (32N), 5 Northeast (5NE), 5 North (5N), 8 North(8N), 8 Deep (8D), Terry Zone North (TZN), 8 South (8S), 8 South Extension (8Sx), Terry Zone (Old Marigold), Top Zone, HideOut, Terry Complex (Battle, Red Rock, East Hill), Red Dot, Mackay, Mud, Target, Valmy, Basalt-Antler, East Basalt, and Battle Cry. The majority of these individual mineralisation zones have coalesced into the Mackay pit.

The gold deposits at Marigold cumulatively define a north-trending alignment of gold mineralised rock more than 8 km long.

Gold mineralizing fluids were primarily controlled by fault structure and lithology, with tertiary influence by fold geometry. Within the Valmy Formation, higher gold grades are observed in th ........

Marigold uses standard open pit mining methods at a LOM sustained mining rate of approximately 250,000 tpd. The mine conducts conventional drilling and blasting activities with a free face trim row blast to ensure stable wall rock conditions. Electronic detonators are used to control the timing of the blasthole detonation.

Drilling and blasting occurs on 15.2 m benches. One grade control sample is taken from each blasthole with the sub-drilling excluded. Mining occurs on 15.2 m benches when prestripping waste or mining ore areas with the P&H electric shovel. 7.6 m benches are mined using the smaller hydraulic shovels to minimise the dilution that would otherwise occur from dozing a 15.2 m high face to these smaller shovels Blasting is done with an ammonium nitrate and fuel oil (ANFO) blend and a sensitised ANFO emulsion. The ore control mark-out procedure includes blast movement analysis for 90% of ore production blasts.

The Marigold geotechnical management plan (GMP) includes highwall monitoring using three radar systems which provide full coverage for the (largest) Mackay pit, or can be deployed in smaller pits, if required. Routine monitoring of waste dumps, leach pads and inactive pits using INSAR data is performed by a third party on a monthly basis.

Loading operations are currently performed using one electric shovel and three hydraulic shovels. Waste and ore haulage is performed with a fleet of 300 t primary haul trucks.

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