picture 1: Collecting of ore on the surface hollows and flat fault pits
picture 2: Ore mining from deeper pits which were drained by a small gallery (even at that early phase hauled by little reel shafts)
picture 3: Installing an upper gallery reaching the ore lode (drainage and perhaps mining)
picture 4: Installing a deep gallery on the valley floor (drainage and mining)
picture 5: Sinking an open shaft for mining, drainage by bottom gallery
picture 6: Changing to underground mining by sinking an open shaft or blind shaft