Geology, alteration and mineralisation styles at Chalcobamba. Following the Ferrobamba traverse, the group was taken to the Chalcobamba deposit, 7.5 km to the NW. In contrast to Ferrobamba, which has only limited magnetite skarn, magnetite is abundant at Chalcobamba. The group spent time at several sites across the deposit studying the various skarns and their inter-relationships. Some of the principal alteration and mineralisation styles and relationships are illustrated above: Top: The Chalcobamba skarn deposit forms a prominent ridge; Middle left: Characteristic exposures of magnetite-rich skarn (dark rocks) on the hill on the right side of the top image; Lower left: magnetite-garnet-epidote endoskarn; Lower centre: mineralised magnetite-garnet-epidote endoskarn; Middle right: Magnetite replacing prograde garnet exoskarn; and Lower right: sulphides replacing both prograde garnet and the overprinting retrograde magnetite in the exoskarn. In the same area, late garnet can also be seen overprinting prograde garnet, retrograde magnetite and sulphides.       Images by Mike Porter.