Reef-type PGE-Ni-Cu Mineralization - Stillwater West contains another mineralization style that is common in layered magmatic systems, the narrower but higher-grade Reef-type deposits. Historically, the majority of the world's supply of platinum group elements has been sourced from mines of this type, and the close proximity of Sibanye-Stillwater's world-class J-M Reef deposit makes Stillwater West highly prospective for high-grade PGE-Ni-Cu reef deposits. The 2023 drill campaign intersected two wide zones of chromite-rich pegmatoidal pyroxenite/harzburgite associated with PGE+Au+Ni+Cu mineralization within the lower part of the Peridotite Zone of the Stillwater Layered Complex correlated with the known A and B Chromitite seams. These mineralized zones have been intersected in five of the six holes drilled during 2023.

In drill hole CM2023-01, the B-Chromitite contains 2.1 meters at 2.58 g/t 3E and 0.20% Ni+Cu+Co starting at 139.6 meters. In drill hole CM2023-03, the B-Chromitite contains 2.50 g/t 3E and 0.35% Ni+Cu+Co over 1.8 meters while the A-Chromitite contains 2.4 meters at 3.50 g/t 3E with 0.21% Ni+Cu+Co including 1.2 meters at 6.83 g/t 3E and 0.20% Ni+Cu+Co. Similarly, the A-Chromitite in hole CM2023-05 contains two high-grade intervals: 2.3 meters at 3.93 g/t 3E and 0.54% Ni+Cu+Co starting at 492.04 meters and 1.8 meters at 3.70 g/t 3E and 0.27% Ni+Cu+Co starting at 520.2 meters.

The B-Chromitite contains a high-grade intersection of 1.8 meters at 2.27 g/t 3E and 0.31% Ni+Cu+Co starting at 298.7 meters. These high-grade intervals are all within wider zones of PGE+Au+Ni+Cu+Co mineralization. Drilling in 2023 confirmed continuity of the stratiform pegmatoidal reef-type "A-B" chromitite zone discovered on Chrome Mountain, providing an important foundation for follow-up drill campaigns.

As reported May 23, 2024, drillhole CM2023-05 also intersected two chromite-rich high-grade PGE horizons towards the bottom part of the hole. These zones returned significant PGE+Ni-Cu mineralization characteristic of the stratiform reef-type high-grade "A-B" chromitite, containing a high-grade zone of 2.79 g/t PGE+Au, plus also 0.31% Ni, 0.20% Cu, and 0.018% Co over 4.8 meters in hole CM2023-05.