Further Massive Sulphides, page-15

haha you have to laugh at the downrampers; only aspect I didn't like was no idea of the %.

Supergene: Metals that have been leached from the oxidized ore are carried downward by percolating groundwater, and react with hypogene sulfides at the supergene-hypogene boundary. The reaction produces secondary sulfides with metal contents higher than those of the primary ore. This is particularly noted in copper ore deposits where the copper sulfide minerals chalcocite Cu2S, covellite CuS, digenite Cu1.8S, and djurleite Cu31S16 are deposited by the descending surface waters.

I'll refer you to this diagram from Dr Google and test it against what the companies geo has been saying about his understanding of the geology (yes yes volcanic activity could have shifted the primary and enriched zones - so its unlikely the deposit would still follow the form of the diagram.