Miitel Nickel Mine
Mincor acquired the then partially developed Miitel Mine from WMC Resources Ltd in 2001 and put it into production that year as the Company's first mine. To end September 2012 Miitel had produced 2.03 million tonnes of ore at an average grade of 3.01% nickel, for 61,000 tonnes of contained nickel. With past production added to June 2012 ore reserves, Miitel's total known nickel endowment is in excess of 70,000 tonnes of nickel metal, and with future exploration success may ultimately exceed 100,000 tonnes of contained nickel metal - making Miitel one of the more significant of Kambalda's ore bodies.
The Miitel ore body has an elongated, near vertical but gently plunging configuration, making it ideal for mining. The channel structure that hosts the ore lenses has proved very continuous. Mincor discovered the North Miitel ore body in 2002 and the South Miitel ore body in 2005, and has continued to extend these discoveries ever since. The overall mineralised system remains open to the north and south and subject to ongoing exploration.
Miitel - Long section showing channel structures
Following an 18-month period of suspended operations due to the global financial crisis, Miitel resumed production in July 2010. A year later Mincor changed the operational structure, moving away from the use of contractors for underground operations and converting the mine entirely to owner-operations with a residential workforce. This proved successful in bringing costs down and mining quality up, and Miitel continues today as a robust operation with a competitive cash cost of production.
Mariners Nickel Mine
The Mariners Nickel Mine was discovered and operated by WMC Resources Ltd between 1991 and 1999, over which period it produced 1,114,730 tonnes of ore at 2.53% nickel for 28,190 tonnes contained nickel metal. It was closed by WMC and written off in 1999 due to flooding which coincided with a period of low nickel prices. Mincor acquired the project at no cost as part of its acquisition of the Miitel Nickel Mine in 2001.
Mincor carried out feasibility studies on reopening Mariners during 2002 and 2003, and gave the project the go-ahead in 2004. After six months of pumping, the mine was de-watered and mining commenced.
Since then, and to September 2012, Mincor has extracted 1.14 million tonnes of ore at 2.6% nickel for 29,600 tonnes of contained nickel.
Mariners - long section
In October 2011 Mincor changed the operational structure at Mariners, moving away from contractors for underground operations and shifting to an entirely owner-operated model with a residential workforce. Costs and quality have improved as a result and Mariners continues today as a low-cost and efficient mine.
McMahon Nickel Mine
The original McMahon Decline was developed by WMC Resources Ltd and used to mine the McMahon ore body, and subsequently a number of other ore bodies that were discovered and mined from the same decline. By June 2007 approx. 1.7 million tonnes of ore had been hauled to surface using the McMahon decline, from the mining of seven different ore bodies.
During 2007 Mincor carried out scoping studies, resource confirmation drilling, and later a full-scale feasibility study. This work examined the feasibility of mining the McMahon Deeps and Ken Far North ore bodies.
In November 2007 Mincor took the decision to develop the ore bodies, for a total projected capital cost of $23 million. The revised Mineral Resource totalled 373,656 tonnes of ore at an average grade of 4.1% nickel, for a total of 15,170 tonnes of nickel metal. Approx. half this Resource has been placed into the initial Ore Reserve, some 7,734 tonnes of nickel metal.
In late 2008, following the collapse in the nickel price induced by the global financial crisis, Mincor suspended development of the decline at McMahon but continued mining reserves that had already been accessed. During 2010 Mincor restarted the main decline, and accessed the high-grade MNO3 ore body in December 2011.
The mine is operated on an owner-mining basis by Mincor, and run as a twin operation with the Otter Juan Mine. This structure captures significant cost savings by maximising the synergies between the two operations, which lie in close proximity to each other.
Otter Juan Nickel Mine
The Otter Juan Mine is Kambalda's oldest producing mine and by far its largest single ore deposit. The mine has been in near-continuous operation since 1970 and to end-December 2010 had produced approximately 8.73 million tonnes of ore at an average grade of 3.58% nickel, for over 313,000 tonnes of nickel metal. Mincor acquired the Otter Juan Mine in July 2007 through its acquisition of the privately owned company, GMM Pty Ltd.
Otter Juan is an owner-mining operation and is operated by a skilled residential workforce of Mincor employees. The mine is now nearing the end of its life, and while profitable mining continues at low production rates, it is expected to close during the 2013 financial year.
However, the ore body is structurally complex, and is the strongest and most consistently mineralised channel structure in the Kambalda District. The structural complexity provides many opportunities for the discovery of additional ore lenses, and this remains an ongoing focus for Mincor's exploration team.
McMahon/Durkin and Otter Juan (showing channel structures)
Apart from the down-plunge extensions of the main ore body, these additional high-grade ore lenses are the subject of ongoing exploration. In addition there is a very substantial remnant mining opportunity which is now being investigated.
Wannaway Nickel Mine
The Wannaway Nickel Mine was discovered in the early 1980s and mined between 1984 and 1998 by WMC Resources Ltd, producing 553,000 tonnes at 2.3% nickel for 12,560 tonnes of nickel metal. The original ore body was mined out by 1998, but WMC discovered a second, higher grade ore body alongside it. Mincor acquired the mine from WMC in 2001, before any mining had taken place in this second ore body.
Mincor commenced mining in late 2001 and by August 2008 the original ore reserves had been mined out and operations were terminated. During this phase of its life Wannaway produced 524,000 tonnes of ore at 3.0% nickel for 15,844 tonnes of contained nickel and 13,931 tonnes of nickel-in-concentrate, generating $141 million in gross revenues.
Significant nickel resources remain below the current level of development, as well as further exploration potential, and the mine is currently on care and maintenance pending higher nickel prices.
Durkin North Nickel Project
The Durkin North mineralisation lies down-dip of the previously mined Durkin ore body, which produced 3.15 million tonnes of ore at 3.26% nickel for 102,740 tonnes of nickel metal between 1969 and 1984.
Mincor has estimated a resource of 378,000 tonnes at 5.1% nickel for 19,400 tonnes of contained nickel metal in Indicated and Inferred Mineral Resources at Durkin North (see above diagram).
Initial scoping studies examined the viability of a mining operation which will access the ore body via a take-off from the existing Otter Juan decline, and indicated a production rate of approximately 2,500 tonnes of nickel metal per annum for an initial period of four years. The project's economics would be strengthened by the addition of reserves closer to the proposed decline take-off from Otter Juan, and further exploration in this area is planned.
Stockwell Nickel Project
The Stockwell Nickel Project lies on the 'Bluebush Line', a series of exploration and mining licences acquired by Mincor in 2008. Work by previous explorers had identified mineralisation at Stockwell, and drilling by Mincor during 2009 outlined a Mineral Resource estimated at 557,000 tonnes or ore at a grade of 3.1% nickel, for 17,100 tonnes of nickel metal.
Pre-feasibility studies have confirmed the potential viability of this project, and further work is underway.