Olivenite with Zincolivnite

A lovely example of the transitional supergene mineralogy that is so typical of the multiphase deposition of the arsenate minerals at the Tsumeb mine. Here on the edge of the crystals, we can see the zinc rich Olivenite becoming gradually less zinc rich as the crystals grew, ending up with a dark olive green copper rich olivenite which has a very low zinc content. This is an old time specimen.