Hence, the only way of getting hold of low-background steel is to find a source of the metal that dates back before those first nuclear tests in 1945. Old sunken battleships are a particularly popular source. Some of the steel from wreckages of German ships scuttled at Scapa Flow in the First World War is believed to have been removed and forged into medical equipment. And there is a roaring trade in metal piracy from old warships, especially in the South China Sea.[18]
