Parks Reef Resource doubles in size to 6.0Moz 5E PGM
Podium Minerals Limited announced a new Mineral Resource Estimate (MRE) at its 100% owned Parks Reef PGM Project in Western Australia. The Inferred resource for the PGM reef now contains 6.0Moz of 5E PGM. The updated PGM horizon contains 0.64g/t platinum (Pt), 0.52g/t palladium (Pd), 0.07g/t Au, 0.05g/t rhodium (Rh) and 0.02g/t iridium (Ir) including 94kt copper (Cu), 127kt nickel (Ni) and 24kt cobalt (Co).
The revised MRE is the result of drilling the Exploration Target (the Stage 10 drilling programme) of 70Mt to 75Mt at 1.2g/t to 1.6g/t 3E PGM at a nominal reef vertical intercept depth of 150m to extend the Inferred resource to 250m below the surface. The orebody remains open below this depth along the full 15km strike. The new MRE for the platinum group metal (PGM) horizon at Parks Reef has been lifted to 143Mt for 6.0Moz at 1.30g/t 5E PGM.
The limits of the PGM Domain (nominally constraining 5E PGM grades of 0.5g/t and above) have been chosen as the cut-off because preliminary mining and metallurgy studies have indicated that material within this domain has a reasonable prospect for eventual economic extraction. The 3D modelling of the resource is based on grade boundaries of 0.5g/t 5E PGM (PGM reef) and 2.0g/t 5E PGM (High-Grade Zone(s)). The MRE now includes a high-grade PGM subset defined on an elevated cut-off of 2g/t 5E PGM The high-grade subset is the addition of two defined high-grade zones that sit within the boundary of the PGM reef, the high-grades zones sit close to the hanging wall of the orebody, the footwall of the orebody and along the 15km strike.
The high-grade zones host 15.7Mt for 1.17Moz at 2.32g/t 5E PGM (1.27g/t Pt, 0.84g/t Pd, 0.14g/t Au, 0.04g/t Rh and 0.03g/t Ir). The orebody shows some variation in orebody widths and grades and the definition of these high-grade areas along with reef width will be an important step in future work including definition of infill drilling, exploration drilling programmes, optimising mining methods and refining processing pathways. It highlights a close association between cut-off grade and the resource reported within the modelled PGM reef and High-Grade Zone(s), this adds to the overall confidence in the resource model.
The grade-tonnage is important for early-stage mine planning as the studies team can evaluate the amount of ore tonnes associated with a range of cut-off grades. The model will also inform where these ore tonnes are situated along the 15km strike length of the Parks Reef orebody. The Parks Reef deposit occurs within the Weld Range Complex (WRC) on the north-western flank of the Weld Range Greenstone Belt.
The WRC is a lopolithic shaped intrusive complex that strikes northeast, dips steeply to the southeast and has a strike length of approximately 15km. The reef itself has high continuity and is present along its entire 15km length and is open at depth. It dips steeply to the south-southeast (SSE) and has an average width of 20-25m in the west, approximately 20m width in the central area, and 10-15m width in the east.
Two high-grade zones that exist also exhibit high continuity, one in the upper part of the reef (hanging wall) and one in the lower part of the reef (footwall). Both zones appear to be consistent in width. The WRC can be grossly divided into ultramafic and mafic zones, with the reef occurring within the ultramafics.
Similarities exist between ultramafic cumulates of the WRC and those of the other large PGM occurrences in South Africa (Bushveld Complex) and in the US (Stillwater Complex), that supply a significant proportion of the current global PGM production. The similarities include the presence of “stacked” high grade zones generally a metre or so wide, and consistency in grade and widths over large distances both along strike and down dip. Unlike these South African occurrences, Parks Reef does not have the occurrence of high chromite grades associated with the thin, metre-wide chromatite bands in proximity to the high-grade PGM occurrences.
As announced when the MRE was upgraded to include rhodium and iridium, a relatively small concentration of the Rh and Ir can drive a meaningful uplift to the weighted average price per 5E PGM ounce of the orebody. Over the past year, the rhodium spot price has traded around $15,000 USD/oz and has been higher than $20,000 USD/oz. Similarly, iridium also commands a high value, recently trading between approx. $6,000 – $4,000 USD/oz. The high value of these elements could add significant value to the final project when the material is either smelted or refined, provided that an economic processing path can be defined. The value proposition of the Parks Reef is exciting, with the potential for 8 payable metals to play a part in the final product mix.