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 December 2010 Miitel had produced 1.81 million tonnes of ore at an average grade of 3.1% nickel, for 56,000 tonnes of contained nickel. With past production added to June 2010 ore reserves, Miitel's total known nickel endowment is in excess of 72,000 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 since early 2010 has made substantial new discoveries further to the south. 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. The mine is largely mechanised and operated on a contractor basis, with Mincor personnel providing mine management, planning, engineering, geology and survey services while the drilling, blasting, bogging and trucking to surface is done by a contracting company under Mincor's supervision.
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. Mining takes place at a depth of around 1,400 metres below surface. Level development is done using jumbo drilling machines but stoping is carried out using hand-held mining techniques. Due to the depth of operation, approximately 30% of the ore is left as pillars to provide stability to the rock mass.
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 historically many small but very high-grade lenses have supplemented production.
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.
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 December 2010, Mincor has extracted 950,000 tonnes of ore at 2.5% nickel for 23,500 tonnes of contained nickel.
Mariners - Long section
Mincor operates the Mariners Mine via a mining contractor. Mincor provides mining engineering, planning, surveying, geological and management expertise, while the contractor carries out the drilling and blasting and the transportation of the ore to surface. The mine is largely mechanised.
The exploration potential at Mariners Mine is very high. During 2006/07 Mincor discovered the N09 ore body, which is now in production. During 2009/10 Mincor discovered the high-grade N10 ore body, which is scheduled to commence production towards the end of 2011. Exploration continues and there are good indications that a further ore body (the N11) is present below the N10.
Carnilya Hill Nickel Mine
The Carnilya Hill Nickel Mine was discovered in 1974 and operated between 1980 and 1999, initially as a joint venture between WMC Resources Ltd and BHP Ltd. It was closed in 1999 on exhaustion of the then known ore reserves, having produced 1.4 million tonnes of ore at 3.37% nickel for 47,290 tonnes of nickel metal.
View Resources Ltd acquired the operation in 2003 and between 2003 and 2005 carried out limited remnant mining. Mincor approached View in late 2005 and the companies agreed on an exploration joint venture under which Mincor would sole fund $2.5 million of exploration expenditure to earn a 70% interest in the project.
Mincor commenced drilling in April 2006, and the discovery hole (10.70 metres @ 6.95% nickel) was drilled in late June 2006. Mincor then commenced a detailed drill-out of the new discovery, and had feasibility studies underway by early 2007. By October 2006, Mincor had earned its 70% interest in the project, and a joint venture was constituted between Mincor and View.
In early June 2007, less than one year after the discovery hole was drilled, Mincor announced formal approval for the development of a $28 million mining project at Carnilya Hill, with initial ore reserves of 483,500 tonnes @ 2.9% nickel. Since then Carnilya Hill has produced 7,900 tonnes of nickel metal contained in 244,000 tonnes of ore at a grade of 3.2% nickel. Mining is expected to continue through until early to mid-2012.
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 approximately 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. Approximately half this Resource has been placed into the initial Ore Reserve, some 7,734 tonnes of nickel metal. The remainder of the Resource, being the Ken Far North ore bodies, require further drilling before they can be included in Ore Reserves. This drilling will be done from underground once suitable access is obtained.
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 is currently pushing it down to the high-grade MMN3 ore body, which is expected to commence production in late 2011.
The mine is operated on an owner-mining basis by Mincor's team at Otter Juan, and run as a subsidiary operation to Otter Juan. This structure captures significant cost savings by maximising the synergies between the two operations, which lie in close proximity to each other.
Coronet/McCloy Nickel Mine
Mincor acquired the Coronet and McCloy mining operations in July 2007 as part of its acquisition of private company, GMM Pty Ltd. Coronet was discovered by WMC Resources Ltd in the early 1990s and put into production by that company in 1995. McCloy was discovered later, and developed by GMM. To end June 2007, the two ore bodies had produced approximately 62,000 tonnes of ore at a grade of 2.85% nickel for 17,700 tonnes of nickel metal. Both ore bodies are mined as subsidiary operations to the bigger operation at Otter Juan.
Although mining at Coronet and McCloy was originally scheduled to terminate in July 2007 due to the exhaustion of known reserves, additional reserves have been discovered, and it now seems likely that mining will continue well into 2011. In addition, Mincor has commenced an extensional exploration program which, if successful, could extend the life of these operations well beyond that date.
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.