Golden Swan Drill Core Demonstrated Excellent Results
Poseidon Nickel (ASX:POS) has received “excellent” metallurgical results received from the preliminary testwork on drill core from the Golden Swan project in Western Australia.
A metallurgical composite sample was prepared from the core from diamond drill hole PBSD0030B, which intersected massive and disseminated nickel mineralisation from 691m down hole. The assayed interval was 9m (4.5m true width) at 10.46% Ni.
Conventional rougher/cleaner flotation with a single stage of cleaning produced saleable concentrate grading 13.6% Ni with 95.1% recovery and an Fe:MgO ratio of 10.2. Incorporating of a pre-float stage to remove naturally floating minerals, prior to the sulphide flotation, produced saleable concentrate grading 14.1% Ni with 93.9% recovery and an Fe:MgO ratio of 50.5.
The composite sample was prepared by Strategic Metallurgy Pty Ltd with guidance from the company. The sample intervals were obtained from quarter core from drill hole PBSD030B (downhole interval 691.8m to 704.8m). The sample selection was guided by an experienced mining engineer and geologist employed by the company to ensure the appropriate representation of anticipated true-width mining dilution. The metallurgical composite comprised the following downhole intervals from PBSD0030B:
- 0.94m felsic footwall (<0.1% Ni)
- 5.70m massive sulphides (12.2% Ni)
- 2.53m stringer and blebby sulphides in ultramafic (1.5% Ni)
- 0.74m massive sulphides (17.4% Ni)
- 2.06m blebby sulphides in ultramafic (1.1% Ni)
- 1.00m ultramafic, weakly mineralised (0.8% Ni)
The objective of the testwork programme was to assess the response of the sample to conventional sulphide flotation techniques. The testwork was undertaken by Strategic at its laboratory in Perth.
The Golden Swan sample responded well to flotation, yielding a high recovery of nickel to saleable grade concentrate. The head grade of the sample is high with respect to both nickel and sulphur confirming the massive sulphide nature of the sample. Given the high nickel grade, obtaining saleable concentrate (nominally >13% nickel) is relatively straightforward, with and without a single stage of cleaning.
The natural flotation of the Golden Swan sample (pre-float with no reagents) yielded a relatively high mass pull to a concentrate (9.5% Ni) grading 21.0% MgO (Test JR05). The pre-float concentrate resulted in only a 1.86% Ni loss.
Visual observations indicate that the naturally floating material is talc-like, however this requires mineralogy to confirm. Subsequent sulphide flotation yielded a 13.1% Ni concentrate and cleaning improved the grade to 14.1% Ni at 93.9% recovery with a very high Fe:MgO ratio of 50.5 (Test JR06). This excellent result highlights the potential to utilise a pre-float stage prior to conventional flotation to significantly improve the Fe:MgO ratio.
