Miracle Upon Miracle Investments (MUM), the private company which owns the rights to the Bengwenyama PGM project through a joint ownership structure in which Southern Palladium holds a 70% stake in MUM, and the remaining 30% is held by Nurinox Investments (Pty) Ltd. a company wholly-owned by the local Bengwenyama community.
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Summary:
Geology
The Project Area is located in the Bushveld Complex (“BC”), the largest layered igneous complex in the world, dated between 2.06 billion years and 2.058 billion years. Located in the north-central Kaapvaal Craton, the BC comprises a mafic-ultramafic succession of layered and massive rocks known as the Rustenburg Layered Suite (“RLS”), granitic rocks called the Lebowa Granite Suite, and felsic extrusive rocks of the Rooiberg Group. The BC was intrusively emplaced within and exhibits a transgressive relationship to the Transvaal Supergroup sequence. It outcrops in three main arcuate complexes, or limbs namely, Western, Eastern, and Northern Limbs. The magmatic layering of the ultramafic-mafic rocks is consistent and can be traced over hundreds of kilometres of strike.
The Bengwenyama Project Mineral Resource consists of the Merensky and UG2 Reefs. Recent completed drilling intersected both reefs which are separated by a 260m middling of norite and pyroxenite units as shown the stratigraphic column of the Project Area. Although both reefs are of economic importance in the region with the Merensky Reef located at shallow depth, sub-cropping in parts, previous studies have indicated that the UG2 is economically the more economic target. Accordingly, the UG2 Reef is the focus of the PFS. Subsequently, although mention is made of the Merensky Reef, the bulk of all reference in the geology and Mineral Resources section in this report has been centred around the UG2 reef.
The UG2 stringers that often appear regionally in the hanging wall of the UG2 are not present in the Project Area. Occurrence of the stringers within the Project Area is localised to a small area in the northeastern corner on Eerstegeluk. The hanging wall contact is an approximately 3 cm thick Leuconorite Parting Plane (“LPP”) overlain by a feldspathic pyroxenite unit. The LPP is not always present resulting in a sharp contact between feldspathic pyroxenite and Chromitite seam. The footwall contact is either a sharp contact or gradational disseminated chromite contact. The footwall of the UG2 is a pegmatoidal or poikilitic feldspathic pyroxenite, with low and variable PGE grades, grading into a medium grained massive feldspathic pyroxenite.
The focus of the PFS is the UG2 Reef which is a chromitite seam of the upper group within the critical zone running at an average reef width of approximately 73 cm.
Mineralisation
The UG2 occurs as either a pure chromite or a cumulate framework of chromite with interstitial plagioclase and/or orthopyroxene. The bulk of the PGE mineralisation associated with the UG2 is hosted within the main chromitite layer as disseminated sulphides attached to the chromite grains. Typically, the sulphides form embayments in the chromite grains or at triple junctions. Less commonly, the sulphides may be occluded within the chromite grains. The typical sulphides which host the PGE are pyrrhotite, pentlandite and chalcopyrite. The UG2 in this area of the BC is characterised by a Pt and Pd telluride assemblage and Pt-Rh-Co-Cu sulphide assemblage. The PGE grades are typically elevated at the top and basal contacts of the chromitite seam. The disseminated mineralisation may extend into the footwall units and is typically related to disseminated chromite and chromitite stringers.
Suntech Geomet Laboratories completed a comprehensive mineralogical characterisation on UG2 chromitite reef samples from drillhole E035 and E077 to characterise PGM minerals utilising geochemical and mineralogical analyses, such as X-ray diffraction analysis and automated scanning electron microscopy mineral liberation analysis.
UG2 reef on drillhole E077 assayed 5.91 g/t 6E, a Pt/Pd ration of 0.57 and Ru index of 16.6% and was dominated by oxides, primarily presented by chromite (~75.2% mass), silicates (~24% mass) comprising plagioclase, orthopyroxene, chlorite, amphibole, talc and mica while the sulphides are only 0.18% mass and other trace minerals. The bulk of the PGMs contained in the sample are PGE-sulphides (~59.3%), while the remainder encompasses PGM Laurite (~16.8%), PGM Bismuth Tellurides (~12.8%), PGMs sulphur-arsenides (~9.3%), and PGM arsenides (~1.9%). PGMs particle grains are 79%- 6.0µm, with the coarsest grain sized at 18µm.
The sample’s base metal sulphide concentration was significantly low (0.18% total sulphides). The sulphides are hosted by pentlandite (~55.53%), chalcopyrite (~37.37%), other sulphides and pyrite (~7.10%).
UG2 reef on drillhole E035 assayed 8.05 g/t 6E, a Pt/Pd ration of 0.98 and Ru index of ~13%, was dominated by oxides, primarily represented by chromite (~89 mass%) and silicates (~11 mass%). The bulk of the PGMs contained in the sample are PGE-sulphides (~84%), while the remainder encompasses PGM Alloys (~6%), Laurite (~6%), PGM Bismuth Tellurides (~2%), and PGM Antimonides (~1%). PGMs particle grains are 50%- 6.8µm, with the coarsest and smallest grains sized at 32µm and 0.52µm respectively.
The sample’s sulphide concentration was significantly low (0.08% total sulphides), with Total S value for the sample of 0.03 wt.%. The sulphides are hosted by pentlandite (~61%), chalcopyrite (~22%), other sulphides and pyrite (~9%). The total sulphides present in the sample are pointedly fine-grained with a D50 of ~13.5µm, 89% of which are liberated while 4% are middlings and the balance locked.
The Merensky Reef is a pyroxenitic unit characterised by enclosing chromitite stingers. The economic portion of the Merensky Reef is typically demarcated by the chromitite stringers. The PGE mineralisation of the Merensky Reef is typically associated with base metal sulphides and silicates. The base metal sulphides are interstitial together with plagioclase feldspar within cumulate orthopyroxene. The PGE mineralisation typically occurs in combination with sulphides, sulpharsenides, arsenides, tellurides and alloys.
The target UG2 and Merensky reefs occur within the Upper Critical Zone of the Rustenburg Layered Suite of the BC. These reefs are laterally continuous for tens to hundreds of kilometres. The UG2 comprises mineralised chromitite, whereas the Merensky Reef is defined as the mineralised pyroxenitic zone between upper and lower chromitite stringers. The BC is the world’s largest igneous intrusion and also the largest global repository of PGEs and chromitite. Both reefs are stratiform with relatively minor disruptive structural features and replacement deposits.
Dimensions
The Bengwenyama project covers an area of approximately 52.9km2. with a strike of approximately 4km. Data from the drillholes suggests a down-dip continuity of UG2 and MR reef over approximately 11km at an average true dip of approximately 6-7°, north-west. A typical West-East cross section through the deposit showing separation of the UG2 and Merensky reefs is provided below. This section does not show the dome structure to the south of Eerstegeluk.
Location of the UG2 reef is shallowest in the south-east corner of the project area at approximately 30m below surface and deepest in the north-west corner where it is in excess of 1,000m below surface. The MR is approximately 260m above the UG2 reef and subcrops in the central portion of the farm Eerstegeluk.