The approximately 40 meter high vein in the belly of "Schwarze Wand" (black rock wall) was vertical and contained galena, chalcopyrite and pyrite. The access to the vein of ore was made roughly in its central part. First the miners dug upwards, then they continued working downwards. Up to 450 miners worked in the belly of the mountain - as tradition reports. The processing plant with stamp mill was located at Lake Puchersee, where it was possible to take advantage of hydroelectric power: here the ore was crushed, which was first chiseled out of the mountain at an altitude of about 2500 m. The smelting of the ore, already separated from quartz material and waste rock, took place in Oetz next to the mouth of Auer Klamm ravine in the so-called "Teufelsschmiede" (devil's smithy).
Today, the tunnel is no longer accessible, entry to the mine is strictly PROHIBITED! Therefore the entrance is blocked with a massive steel lattice door. In front of the entrance to the mine, however, hikers repeatedly find slag originating probably from a tool smithy where the tools of the miners were reworked again and again.