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Australia

Mount Monger Operation

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Australia

Mount Monger Operation

Location: 64 km SE from Kalgoorlie, Western Australia, Australia

Address:

Suite 4, Level 3, South Shore Centre
85 South Perth Esplanade, PO Box 876, South Perth WA 6951
Perth
Western Australia, Australia
6151

Contacts:

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Categories

Summary

Mine TypeOpen Pit & Underground
StatusActive
Commodities
  • Gold
Mining Method
  • Truck & Shovel / Loader
  • Longhole stoping
  • Longhole open stoping
  • Airleg stoping
  • Longitudinal open stoping
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SnapshotThe Mount Monger operation is divided into three main independent Mining Centres: Daisy, Mount Belches, and Aldiss Mining Centres. These three Mining Centres feed the Randalls processing facility.

The Daisy Mining Centre includes the Daisy Complex underground mine as well as surrounding projects such as Mirror/Magic and Lorna Doone.

The Mount Belches Mining Centre includes Maxwells underground mine, Cock-eyed Bob underground mine, and the Santa Complex.

The Aldiss Mining Centre includes the Karonie, Tank/Atreides and French Kiss projects.

Run of mine production during FY25 will be primarily sourced from open pit mining at the Santa Mining Centre (Mount Belches Centre), supplemented by the French Kiss (Aldiss Mining Centre) cut back and high grade underground ore from the Daisy Complex.
Related AssetsAldiss Centre Mine, Daisy Centre Mine, Mount Belches Centre Mine

Owners

SourceSource
CompanyInterestOwnership
Vault Minerals Ltd. 100 % Indirect
Mount Monger Operation is indirectly wholly owned by Vault Minerals Limited.

The Vault Minerals Limited has been decided as the new name of the merged Red 5 Limited and Silver Lake Resources Limited following their merger in June 2024. All Silver Lake shares have been transferred to Red 5.

Contractors

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SourceSource

Deposit type

  • Metamorphic
  • Vein / narrow vein
  • Banded iron formation hosted
  • Porphyry

Summary:

DAISY COMPLEX
The Daisy Mining Centre lies along the Bulong Anticline within the Gindalbie Terrane of the Norseman-Wiluna Greenstone Belt. The core of the Bulong Anticline (the Yindarlgooda Dome) contains mineralised granitic intrusive rocks in a sequence of felsic to intermediate conglomeratic sedimentary rock, structurally overlain by a mafic-ultramafic succession. Quartz-feldspar porphyry dykes and sills intrude the sequence.

A northwest striking (50°), south dipping shear (the Godard Shear) separates the ultramafic sequence to the south from the felsic volcaniclastic rocks to the north. The structural setting of the Daisy Complex is analogous to that of the Kanowna gold mining centre, with is located on shears spaying away for the regional Kanowna Shear.

Mineralisation occurs along north–south trending, transpressional structures, commonly along or associate with the Main porphyry contacts and/or north–south shear structures. Haloes of sericitepyrite-fuchsite alteration around mineralised quartz carbonate veins typically highlight metal-rich fluid pathways. Galena and sphalerite are generally enriched in typical Daisy ore veins and compressional shear structures on vein margins are also excellent indicators of gold mineralisation.

Mineralised veins are typically subvertical, vary between 0.05 m and 1 m in width, generally trend north–south and exhibit significant wall rock alteration. Milky white (bucky), often wide (>2 m) nonmineralised veins trend east–west, have significant alteration halos and cross-cut ore mineralisation.

MOUNT BELCHES CENTRE
The Mount Belches area is underlain by the Mount Belches greywacke and lies between the Mulgabbie and Kurnalpi terranes to the east and the Gindalbie and Kalgoorlie terranes to the west. The Mount Belches greywacke is bound by the Mount Monger Fault, the Randalls Fault (locally known as the Bare Hill Shear) in the west and the Avoca Shear in the east.

The Mount Belches greywacke forms part of a turbidite sequence which comprises biotite-bearing siltstones, sandstones and greywackes and BIFs.

The known gold deposits at Mount Belches are hosted within several metamorphosed BIF units that form a minor component of the Mount Belches greywacke. Two BIF packages are recognised: a poorly outcropping lower or ‘Maxwells’ package and an outcropping upper or ‘Santa-Craze’ package. Two facies of BIF are recognised in the upper and lower sequences: a magnetite– grunerite-rich6 facies and a magnetite-rich facies.

The gold mineralisation is developed in shallow to moderate south plunging shoots in quartz veins preferentially hosted in both facies of the BIF. Minor amounts of mineralisation are also located in the chloritic siltstones adjacent to these BIF units. Sufidation is the key chemical mechanism controlling gold precipitation, and the iron-rich BIFs present an ideal host. Pyrrhotite is the dominant sulfide and is accompanied by pyrite and arsenopyrite. From petrological analysis, these minerals formed as part of the same metamorphic paragenetic assemblage. Arsenopyrite is commonly present as well-formed crystals up to 1 cm in size.

ALDISS CENTRE
The Aldiss area lies on the eastern margin of the Eastern Goldfields Greenstone Province (EGGP) where Archaean volcano-sedimentary sequences are juxtaposed against granitoid-gneissic terranes. The province is characterised by an interconnecting series of north-northwest trending greenstone belts surrounded by ovoid to elongate granite batholiths. The province differs from adjacent provinces in that it contains a higher proportion of komatiites and a lower proportion of BIF units. The overall stratigraphic succession in the greenstone of the EGGP is characterised by a lower sequence dominated by mafic to ultramafic volcanic and intrusive units, overlain by more felsic volcanics and an upper sequence dominated by felsic sedimentary units of clastic and chemical origin. Structurally the greenstone sequences record a protracted history of deformation that has produced steeply west dipping and north-northwest striking lithological contacts and a well-developed foliation that trends in the same direction.

Gold mineralisation occurs almost exclusively within the quartz amphibolites and occurs dominantly as native gold. The habit of the native gold is as coarse interstitial grains, located along hornblende and quartz grain boundaries or included within the hornblende grains along cleavage. Sulfides are present, with pyrite subordinate to pyrrhotite and lesser chalcopyrite and minor molybdenite. Gold mineralisation is not associated with the sulfides in any way, which is unusual. Mineralisation also occurs within the metasediments but appears to be related to a late-stage event. Visible gold within quartz veins, microscopic gold adjacent to quartz veins and gold associated with minute shear zones suggest that the mineralisation is structurally controlled.

Reserves

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Mining Methods

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Heavy Mobile Equipment

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Comminution

Crushers and Mills

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Processing

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Commodity Production

CommodityUnits2025202420232022202120202019201820172016
Gold koz  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe137 158 136 131 
All production numbers are expressed as metal in doré. ^ Guidance / Forecast.

Operational metrics

Metrics2025202420232022202120202019201820172016
Annual processing capacity  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe1.3 Mt1.3 Mt1.3 Mt
Ore tonnes mined  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe1,419,100 t1,269,722 t1,306,508 t1,286,196 t
Waste OP  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe
Tonnes milled  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe1,229,195 t1,256,120 t1,300,152 t1,236,600 t
Hourly processing capacity  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe

Production Costs

CommodityUnits202520242023202220212020201920182017
Credits (by-product) Gold AUD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe -3 / oz   -5 / oz   -6 / oz  
All-in sustaining costs (sold) Gold AUD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe 1,434 / oz **   1,289 / oz **   1,359 / oz **  
^ Guidance / Forecast.
** Net of By-Product.

Mine Financials

Units202520242023202220212020201920182017
Capital expenditures (planned) M AUD
Capital expenditures M AUD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe 42.8  
Revenue M AUD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe 246.9   255.6   227.5  
Pre-tax Income M AUD  ....  Subscribe
EBITDA M AUD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe 68   87.9   70  

Personnel

Mine Management

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Workforce

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