Mining for metals began as early as 12,000 years ago in the Stone Age in Upper Silesia, in present-day Poland, research on peat bogs has found. Scientists found the evidence for mining in the ancient layers of bog in Miasteczko Śląskie near Tarnowskie Góry in southern Poland. The bog trapped the impurities that prehistoric people washed from the metal ores, researchers say, showing their findings in an exhibition at the Centre of Silesian Culture in the town of Nakło Śląskie.
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