Collerina Nickel-Cobalt Project

The Collerina nickel-cobalt project is located 40 kilometres south of Nyngan in central NSW, covering an area of 300 square kilometres within the Fifield Platinum Province. The tenement contains the Homeville nickel-cobalt deposit, which was discovered by Collerina Cobalt Limited in 2008.

The JORC complaint resource estimate for Homeville is 16.3 million tonnes at 0.93% nickel and 0.05% cobalt (cut-off 0.7% nickel).

The total resource is estimated to contain approximately 151,000 tonnes of nickel and 8,100 tonnes of cobalt.

The mineralisation is at surface in some areas and has an average depth of only 10 metres below surface.

Based on a cut-off of 0.7% nickel, the resource estimate includes a total of 4.4 million tonnes at 0.99% nickel and 0.06% cobalt as Indicated Resource and 11.9 million tonnes at 0.91% nickel and 0.05% cobalt as Inferred Resource. 

Saprolitic and limonitic host mineralisation has also been estimated with 14.3 million tonnes, or nearly 88% of the resource, as saprolite (based on a cut-off of 0.7% nickel). Focus for further metallurgical studies will be concentrated on the saprolitic domain.

Confidence Million Tonnes Nickel Cut-off (%) Nickel (%) Cobalt (%) Iron (%) Magnesium (%)
  27.2 0.5 0.80 0.05 19 9.8
Total 16.3 0.7 0.93 0.05 19 9.3
  4.9 1.0 1.18 0.05 18 8.6
  6.4 0.5 0.87 0.06 21 9.6
Indicated 4.4 0.7 0.99 0.06 20 8.8
  1.8 1.0 1.21 0.05 19 7.9
  20.7 0.5 0.78 0.05 18 9.9
Inferred 11.9 0.7 0.91 0.05 18 9.4
  3.1 1.0 1.16 0.05 17 8.8
Homeville nickel-cobalt deposit resource summary by JORC category.
Confidence Million Tonnes Nickel Cut-off (%) Nickel (%) Cobalt (%) Iron (%) Magnesium (%)
  5.2 0.5 0.69 0.08 27 0.2
Limonitic 2.0 0.7 0.84 0.10 30 1.4
  0.2 1.0 1.14 0.12 33 1.9
  21.9 0.5 0.83 0.04 17 10.3
Saprolitic 14.3 0.7 0.95 0.04 17 10.4
  4.7 1.0 1.18 0.04 17 10.2
Homeville nickel-cobalt deposit resource summary by host type.

 

The Collerina project contains several additional advanced prospects including Yathella (nickel-cobalt), Swanson’s Trouble (gold), C1 (scandium, platinum nickel-cobalt) Widgelands (copper) and the Collerina Mine (copper).

Under the terms of an  agreement exploration and development agreement signed in January 2014, Helix Resources Limited (‘Helix’) secured the sole right to explore the tenement for precious and base metal mineralisation. Helix holds 100% of the precious and base metal rights (excluding Nickel Laterite mineralisation), with Collerina Cobalt Limited retaining a 1.5% net smelter royalty over any discoveries by Helix. Collerina Cobalt Limited retains 100% ownership of the known nickel laterite mineralisation within the Homeville, Yethella and C1 Anomaly areas. 

Testwork

Collerina Cobalt has recently commenced further metallurgical testwork on ore from its Homeville deposit utilising a Counter Current Atmospheric Leaching ('CCAL') process.

Previous CCAL test work returned excellent overall nickel and cobalt extractions of 90% and 96% respectively, with very low overall acid consumption of 710 kg/tonne of ore.

CCAL involves two stages of leaching.  In the first stage, fresh ore is leached in a lower free acid solution, leaching the readily leachable material and producing a pregnant leach solution with relatively low residual acidity. The leach residue solids from the first stage are washed and forwarded to the second stage of leaching.  In the second stage of leaching, concentrated sulphuric acid is used and the more tenacious material is leached by the higher concentration of acid.  The leach solution from the second stage, with a much higher residual acid concentration, is recycled to the first stage leach as the acid source.

High Purity Alumina (HPA) Testwork

The CCAL produces a low acidity leach solution.  After appropriate preā€treatment, the pregnant leach solution will be subjected to testing using a proprietary solvent extraction and refining process with an aim to produce 4N HPA (99.99% purity). The liquor remaining after aluminium extraction contains the cobalt and nickel units that can then be recovered to produce separate high purity nickel and cobalt products (metal, sulphate, carbonate, hydroxide or other forms).

Tenement Update

Collerina Cobalt Limited successfully applied for a 3 year extension for all 50 sub-blocks associated with the project’s EL 6336.  The 3 year extension is timely and allows the project’s potential to be further explored and optimised by improving the current resource base, the commencement of conceptual mine planning, further optimisation of metallurgical testwork, process plant location options and mine infrastructure layout.

Current Drill Program

Assay results have been received for 34 reverse circulation (RC) drill holes at the Collerina project, Nyngan, NSW.

  • Results indicate the occurrence of shallow high-grade Co + Ni mineralisation over significant thickness and length.  Significant intersections include:
    • 46m (8-54m) of 0.11% Co and 0.64% Ni in hole CCR-21, including:
    • 18m (24-42m) of 0.21% Co;
    • 38m (10-48m) of 0.12% Co and 1.01% Ni in hole CCR-22.
  • The results also indicate the occurrence of discrete shallow zones of very high grade Co:
    • 0.56% Co and 0.77% Ni over 4m (40-44m) in hole CRR-23;
    • 0.70% Co and 0.88% Ni over 4m (18-22m) in hole CCR-32, including:
    • a 2m composite assay of 1.02% Co and 1.07% Ni from 18-20 m.
  • The occurrence of high-grade Ni mineralisation is also indicated by intersections of:
    • 28m (5-33m) of 1.48% Ni including 8m (5-13m) of 0.17% Co in hole CCR-18; and
    • 18m (2-20m) of 1.24% Ni in hole CCR-17.
  • The Company is now preparing a bulk composite sample for Counter Current Atmospheric Leaching (CCAL) test work for the recovery of Co-Ni and for further testing of the CCAL Pregnant Leach Solution (PLS) to produce a high purity alumina (HPA) product.