Grasberg
Papua, Indonesia
PorphyriesCu-Au
- Type
- Cu-Au porphyry
One of the largest porphyry deposits in the world, mineralised by successive intrusions.
δ65Cu in ‰ (per mil) Values of the same system
Standard : NIST SRM 976
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 0.02 / 1.34 ‰ | chalcopyrite | Cu isotopes in chalcopyrite from successive intrusions at Grasberg, Indonesia (2010) |
δ56Fe in ‰ (per mil) Values of the same system
Standard : IRMM-014
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| −2 / 1.1 ‰ | sulfides (chalcopyrite and pyrite) A clear difference between chalcopyrite (-1.7 to -0.3 ‰) and pyrite (0.0 to 0.8 ‰), suggesting fractionation between minerals or precipitation at different temperatures or from different fluids. | Graham et al. 2004, Fe isotopes in Grasberg porphyry Cu deposit |
187Os/188Os isotope ratio, no unit Values of the same system
Standard : Rapport absolu, sans standard de référence
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 0.87 | 1 | chalcopyrite of the Main Grasberg Intrusion Initial ratio (187Os/188Os)i; a partly crustal signature, more radiogenic than the mantle. | Mathur et al. (2005), A Re-Os isotope study of sedimentary rocks and copper-gold ores fro… | |
| 0.26 ± 0.13 | Ertsberg skarn and stockwork chalcopyrite Initial ratio from the Re-Os isochron of the Ertsberg sulfides. | Mathur et al. (2005), A Re-Os isotope study of sedimentary rocks and copper-gold ores fro… | ||
| 0.58 / 0.92 | 6 | magnetite and sulfides of peripheral ores (Kucing Liar, DOM) Heterogeneous initial ratios overlapping those of the host sedimentary rocks (0.52 to 2.21): osmium there is partly borrowed from the host rocks. | Mathur et al. (2005), A Re-Os isotope study of sedimentary rocks and copper-gold ores fro… |
Deposits of the same type
- Batu Hijau Indonesia
- Northparkes Australia
- Oyu Tolgoi Mongolia
- Qulong China
- Sharang China
- Jiru China
- Zhuonuo China
- Chagele China
Cite this page
IsoFind Atlas (2026). Grasberg, isotope signatures. https://www.isofind.tech/isotopes/en/deposits/grasberg/ (accessed 2026-10-06).
@misc{isofind2026grasbergisotopesignatures,
title = {Grasberg, isotope signatures},
author = {{IsoFind Atlas}},
year = {2026},
url = {https://www.isofind.tech/isotopes/en/deposits/grasberg/},
note = {Accessed 2026-10-06}
}Updated : 2026-10-06