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The Tumpangpitu porphyry and high-intermediate-sulphidation epithermal deposit is the largest deposit in the Tujuh Bukit district, southeast Java. The porphyry resource contains 1.9 billion tonnes at 0.45% Cu and 0.45 g/t Au, for 28.1 Moz Au and 19 billion lbs of Cu. There are an additional 2.1 Moz Au and 72.9 Moz of Ag in oxidised high-sulphidation epithermal mineralisation. Magmatism, mineralisation, and alteration at Tumpangpitu occurred in response to north-directed subduction of the Indo-Australian plate beneath the Asian continental plate margin. Volcanic-hydrothermal activity at Tujuh Bukit began with the formation of the weakly altered Tanjung Jahe diatreme complex (U-Pb zircon ages of 8.78 ± 0.22-8.52 ± 0.21 Ma). Mineralisation at Tumpangpitu was preceded by the intrusion of a large, equigranular, dioritic batholith (5.81 ± 0.20-5.18 ± 0.27 Ma). Hydrothermal activity associated with mineralisation has been constrained by U-Pb age determinations from syn- to late-mineralisation porphyries that were emplaced in the early Pliocene from 5.40 ± 0.46 to 3.94 ± 0.69 Ma., The Tumpangpitu porphyry and high-intermediate-sulphidation epithermal deposit is the largest deposit in the Tujuh Bukit district, southeast Java. The porphyry resource contains 1.9 billion tonnes at 0.45% Cu and 0.45 g/t Au, for 28.1 Moz Au and 19 billion lbs of Cu. There are an additional 2.1 Moz Au and 72.9 Moz of Ag in oxidised high-sulphidation epithermal mineralisation. Magmatism, mineralisation, and alteration at Tumpangpitu occurred in response to north-directed subduction of the Indo-Australian plate beneath the Asian continental plate margin. Volcanic-hydrothermal activity at Tujuh Bukit began with the formation of the weakly altered Tanjung Jahe diatreme complex (U-Pb zircon ages of 8.78 ± 0.22-8.52 ± 0.21 Ma). Mineralisation at Tumpangpitu was preceded by the intrusion of a large, equigranular, dioritic batholith (5.81 ± 0.20-5.18 ± 0.27 Ma). Hydrothermal activity associated with mineralisation has been constrained by U-Pb age determinations from syn- to late-mineralisation porphyries that were emplaced in the early Pliocene from 5.40 ± 0.46 to 3.94 ± 0.69 Ma.

The vertical distribution of copper, lead, and zinc in the Elk Point evaporite sequence shows a close correlation with the lithology. The highest contents of all three metals are found in the shale, dolomite, and anhydrite of the sequence. Concentrations of heavy metals in the Elk Point evaporite sequence are very high compared to concentrations of the same metals in sea water, by factors of 11 to 826 for copper, 54 to 1130 for zinc and 6000 to 9.02 x 10 5 for lead., The vertical distribution of copper, lead, and zinc in the Elk Point evaporite sequence shows a close correlation with the lithology. The highest contents of all three metals are found in the shale, dolomite, and anhydrite of the sequence. Concentrations of heavy metals in the Elk Point evaporite sequence are very high compared to concentrations of the same metals in sea water, by factors of 11 to 826 for copper, 54 to 1130 for zinc and 6000 to 9.02 x 10 5 for lead.