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Educational Trail Rotava

Exploration Adit

The situation map

We are at the entrance to the exploration adit. Rock massif is built by very solid crystalline rock, quartzite schist, the oldest rock in the area (age of about 350 million years). Traces of the movement of the Earth’s plates and traces of black tungsten ore, which was mined in Rotava in 1939–1950, are concealed in the adit interior.

Inside of the exploration adit

Rotava, it is the geological world a synonym of tungsten. Tungsten ore discovered here in 1928 Anton Frieser in an old adit under the church. After 1934 was at the road in Rotava-Samota excavated exploratory shaft Gerhard and 200 m farther to the southeast the shaft Adelhaid.

The dump of the Adelhaid Shaft

Frieser and his associates, who are heavily hunted capital in an economic crisis, helped World War, when Germany supported extraction of strategic raw materials. The company Egerländer Erzbergbau based in Horní Slavkov operated 1939–1945 in Rotava mine and working camp for extraction and processing of tungsten ore. Geological exploration by underground adits continued simultaneously. After the war, the Czechoslovak state took over the mining. Besides the mine, there worked gravity treatment plant, which from ore with an average content of 0.15 % W produced ore concentrate containing 65 % WO3. Exploration activities continued in the strip Stříbrná-Rotava Jindřichovice up to 1953, but economically recoverable ores have not been found. Exploratory adits and surface excavation are best preserved on the left bank of the Novoveský Creek, on the Sklenský Hill and to the west of Jindřichovice.

The Glasberg Adit (photo by P. Gardner)

The deposit is developed in the granite elevation of elliptical floor plan. Granites are densely permeated by veins of aplite and mineralized quartz. The stockwork built by dense system of veins, which are few centimetres to decimetres thick, decline towards the periphery of the granite body. Ore content disappears at a depth of 45 m. Main ore is wolframite (ferberite), an iron tungstate FeWO4, which consists of heavy black tabular crystals with a metallic lustre.

This text was written by Petr Rojík.

GPS position

N 50° 18.005', E 12° 34.292'
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