Poseidon Nickel (ASX: POS) has announced a highly encouraging update from its Black Swan komatiite channel near Kalgoorlie, Western Australia.
The company reported that new massive Ni sulphide lode named “Golden Swan” was intersected as predicted by EM anomaly within the Black Swan mineralised channel.
POS said that assays are currently prioritised and pending for the 19.5m (11.5m true width) of highly mineralised komatiite including 2m massive Ni sulphides in PBSD0029A from 739.5m down hole.
The company said that the DHEM interpretations are currently underway to assist further drilling.
Black Swan project
The Black Swan Project is located approximately 600km east of Perth and 50km northeast of Kalgoorlie, Western Australia and 300kms South of Poseidon’s Windarra Nickel Project.
The Black Swan project comprises the Silver Swan underground mine, the Black Swan open pit and the Black Swan 2.2Mtpa Concentrator with 191,400t of nickel metal in resource. It may be noted that Poseidon’s re-interpretation of the deposit had culminated in the current Silver Swan Resource.
The Black Swan disseminated and Silver Swan massive sulphide orebodies are separate mineralised komatiite channels with the Silver Swan massive sulphide deposit being formed first, closely followed by the Cygnet deposit and then the Black Swan disseminated deposit.
Drilling at Black Swan
The 2019 DHEM survey by Newexco had identified a large EM anomaly consistent with a massive sulphide EM response at the base of the Black Swan komatiite channel. The anomaly was located in a similar stratigraphic location as the Gosling Massive Sulphide orebody. The high-grade Gosling Operation produced 121,417t @ 4.4 %Ni.
The company reported that it had commenced (Stage 1) staged drilling and EM survey approach to test the recently identified electromagnetic (EM) anomaly.
New Golden Swan nickel sulphide discovery
Poseidon reported that it has now discovered high-tenor massive nickel sulphides in the first hole of the drill program. The company said that the new lode has been named “Golden Swan”.
The company said that the diamond drill hole PBSD0029A intersected 19.5m (11.5m true width) of visual confirmation of nickel-bearing, highly mineralised komatiite including 2m of high-tenor massive sulphides between 739.5m and 759m downhole.
POS said that the intersection is located near the very top of the Golden Swan anomaly which continues for around 150m below the current intersection.
POS reported the estimate and proportions of mineral species present, which was deduced from visual confirmation from the drill core. The company said that the sulphide mineral species identified and proportional estimate by category is Pyrrhotite 50%; Pentlandite 40%; and Pyrite 10%.
Core sent for analysis
Poseidon said that the core has been logged and sampled and is en route to the lab for priority analysis. The company said that the results of the additional review and substantive assays are currently expected within 10 days for separate disclosure.
Located at base of Black Swan
The company reported that the study of the drill core from the current intersection has revealed that the Golden Swan massive sulphides are occurring on the base of the Black Swan channel, making it quite different from the 1996 Gosling discovery.
The company said that the Golden Swan intersection reveals massive sulphides accumulating directly on the Black Swan channel floor which is underlain by an in-tact felsic footwall on its southern edge.
The interpretation of this is that the Black Swan lava flow was widening and slowing down, allowing sulphides to naturally drop to the channel floor without requiring another intervention such as a felsic raft to induce settling. The slowing down would most likely be related to a widening of the channel for which there is good evidence.
The company said that the footwall felsic remains attached to the channel wall and forms the natural floor below the Black Swan komatiite flow.
The implications of this are that the extent of the massive sulphides at Golden Swan is not limited by the size of the transported felsic raft as they were at Gosling, but now by the size and topography of the larger, main channel floor.
The company said that the footwall topography offers natural massive sulphide trap-sites as is observed 400m to the north at the Silver Swan deposit.
Updates and next steps
The company reported that it has now completed Stage 1 tested the DHEM anomaly and has confirmed its width, location and that it contains nickel.
Stage 2: POS announced that Stage 2 will involve a second wedge hole to test the lower portion of the conductor and to provide information on continuity and dip for use in further geophysical modelling.
Stage 3: Poseidon said that in Stage 3, the parent hole used for Stages 1 and 2 will then be extended to 1000m in length (1300m below surface) and cased to allow for further DHEM assessment of the base of the Black Swan channel for massive sulphides.
Poseidon Nickel Managing Director/CEO Peter Harold said: “This is a very significant discovery in the context of Black Swan given it is only the second time significant massive sulphides have been intersected within the Black Swan disseminated channel since the discovery of the Gosling Lode in 1996.
This major achievement is a testament to the efforts of our geological team and particularly our Chief Geologist, Steve Warriner, Neil Hutchison (Geological Consultant) and our geophysics consultants, Newexco. We are very much looking forward to seeing how this new discovery unfolds.”