Great Dyke (Main Sulfide Zone)

Mashonaland West and neighbouring provinces (550 km linear intrusion), Zimbabwe

Magmatic (Ni-Cu-PGE, carbonatites)PGE (Pt, Pd) - Cu, Ni

Type
Stratabound PGE in a layered mafic-ultramafic intrusion (2.58 Ga)

The world's second largest platinum-group element reserve after the Bushveld. The linear intrusion, 550 km long, formed 2.58 Ga ago. The economic mineralisation lies in the Main Sulfide Zone, a tabular layer in pyroxenites at the top of the ultramafic sequence. Active mines are Hartley (Ngezi), Mimosa, Unki and Bohmke Reef.

δ34S in ‰ (per mil) Values of the same system

Standard : V-CDT

ValueRangenMineral or matrixSource
0.1 / 1 ‰pyrite, pyrrhotite and pentlandite (Hartley)
A narrow, slightly positive δ34S range, characteristic of a mantle source with negligible crustal contamination. Distinct from the Bushveld Platreef (+9 to +14.2 ‰), which shows strong assimilation of sedimentary sulfate.
Li et al. 2008, Sulfur isotope variation in pyrite-pyrrhotite-pentlandite of the Great Dy…
−0.3 / 0.3 ‰whole rock (Maier study, 2015)
An even narrower whole-rock range, centred on zero, consistent with a pure mantle signature (0 ± 5 ‰, Ohmoto and Goldhaber, 1997). Very little crustal contamination of the parent magma.
Maier et al. 2015, Sulfur isotope variations across the Great Dyke

Deposits of the same type

Cite this page

IsoFind Atlas (2026). Great Dyke (Main Sulfide Zone), isotope signatures. https://www.isofind.tech/isotopes/en/deposits/great-dyke-zone-sulfuree-principale/ (accessed 2026-10-06).

@misc{isofind2026greatdykemainsulfidezoneisoto,
  title = {Great Dyke (Main Sulfide Zone), isotope signatures},
  author = {{IsoFind Atlas}},
  year = {2026},
  url = {https://www.isofind.tech/isotopes/en/deposits/great-dyke-zone-sulfuree-principale/},
  note = {Accessed 2026-10-06}
}

Updated : 2026-10-06