Rubicon Resources Limited

Warburton Project

The Warburton Project is located at the Warburton Community in the far western Musgrave province, approximately 750 kilometres northeast of Kalgoorlie in Western Australia. The Project comprises 2,900 km² of exploration licences. Rubicon is exploring this largely unexplored terrain for stratabound sediment-hosted copper (eg. Mt Isa and Michigan Copper belt) in conjunction with major Rubicon shareholder Vale Australia EA Pty Limited (a wholly owned subsidiary of Vale).

The West Musgrave area is considered by the Company as highly prospective based on the following:

In February 2008, Rubicon entered into an Evaluation and Farm-in Agreement over the Warburton project with Vale Australia EA Pty Ltd, a wholly owned subsidiary of Companhia Vale do Rio Doce (Vale). Vale has committed to the Farm-in stage of the agreement whereby it is spending $3 million over three years to earn a 51% interest in the project and may exercise an option to enter into an Exploration Joint Venture Agreement with Rubicon. Rubicon is managing the exploration.

Vale may proceed to a 70% interest in the project by sole funding exploration and development studies up to the commencement of a Bankable Feasibility Study (BFS) and an additional 5% interest by sole funding the BFS.

The project is located on Aboriginal Reserve Land and access agreements with the Ngaanyatjarra People for all of the Warburton Copper and Gunbarrel tenements have been negotiated. Heritage clearance surveys for all required work have been completed in an expedient and harmonious manner and Rubicon has been very pleased with its relationship with the Ngaanyatjarra People.

The Warburton Copper Area is located on the partly outcropping southwest part of the Musgrave province, centred on the Warburton community and the Warburton Copper Prospects (Harry Simms Mine). The prospective area is dominantly basalt, sandstone and conglomerates. Copper mineralisation was discovered by prospectors in the early 1960s and the area was the subject of a significant exploration campaign in the late 1960s and early 1970s. Limited mining of narrow chalcocite-rich veins was also undertaken in the 1960s at the Harry Simms mine.

Around 200 copper mineral occurrences and geochemically anomalous soils over a 20 kilometre strike length have been identified. Previous exploration in the area included auger, vacuum drilling and percussion drilling and culminated in the drilling of 12 diamond core holes, of which four intersected significant copper mineralisation, up to 3.5m @ 8.2% copper and 16g/t silver.

Exploration at the Gunbarrel Area has highlighted the potential for copper-nickel mineralisation associated with dyke-sill complexes in the footwall of interpreted Giles Complex equivalent rocks as indicated by gravity and magnetics. Analogous examples are Voisey's Bay in Canada and the Babel and Nebo deposits located southeast of Caesar Hill.

The Caesar Hill tenement is located to the east of the Palgrave Volcanic Complex where the volcanic rocks of the Palgrave are in faulted contact with Giles Complex, immediately northwest of the Babel-Nebo mineralisation and north of a chrysoprase pit (chrysoprase is a nickel-rich silicates). The tenement was explored in conjunction with the discovery of the Babel and Nebo deposits, although there was little work completed on it.

The main exploration targets that have been defined are as follows:

  1. Warburton Copper Target. The 12 kilometre strike of anomalous subcropping copper mineralisation remains a high priority target. Previous drilling focused on narrow re-mobilized high-grade vein occurrences. Surficial copper also occurs in the matrix of conglomerates and in mafic flow top breccias. Analogous conglomerate-hosted deposits in the Calumet and Hecla Conglomerate at Michigan, USA have produced almost two million tonne of copper.
  2. Keeweenaw Target. Keeweenaw is a conglomerate-hosted target located northwest of Warburton. The conglomerate sequence at Warburton Copper is interpreted to continue under cover to the northwest, where the sequence is more complexly displaced by apparent magnetite depleted faults (indicative of potential alteration), than at Warburton itself.
  3. Lilian Target. A magnetically "quiet" zone under shallow sand cover is interpreted as a possible fine grained sediment (sitting above the conglomerate/basalt unit) in a structural and lithological setting that is analogous to that at White Pine (Michigan), which has produced 1.8 million tonne of copper.
  4. Elder Target. As for Lilian.
  5. Jackie Junction Target. Copper-nickel mineralisation target associated with dyke-sill complexes in the footwall of the interpreted Giles Complex equivalent as indicated by gravity and magnetics. Analogous examples are Voisey's Bay in Canada and the Babel and Nebo deposits located southeast of Caesar Hill.
  6. Caesar Hill Target. As for Jackie Junction. This target also has a strong resemblance to the setting of the Babel and Nebo deposits and occurs over sub-cropping basal Giles Complex rocks adjacent to the major Palgrave Volcanic Complex.
  7. Bentley Hill Target. A similar target to Caesar Hill on the western side of the Palgrave Volcanic Complex.

Exploration activities for the project have focused on the Warburton Copper area and have consisted of the following:

Rubicon was awarded a Western Australian Government Co-funded Drilling grant for $148,000 to fund 50% of the RC drill programme and an 800 metre diamond drill hole to be completed in 2010.