LAURIUM (Aabptov, mod. ERGASTIRI)  , a mining town in Attica, Greece, famous for the silver mines which were one of the chief sources of revenue of the Athenian state, and were employed for coinage . After the battle of Marathon, Themistocles persuaded the Athenians to, devote the revenue derived from the mines to shipbuilding, and thus laid the foundation of the Athenian naval power, and made possible the victory of Salamis . The mines, which were the property of the state, were usually farmed out for a certain fixed sum and a percentage on the working; slave labour was exclusively employed . To-wards the end of the 5th century the output was diminished, partly owing to the Spartan occupation of Decelea . But the mines continued to be worked, though Strabo records that in his time the tailings were being worked over, and Pausanias speaks of the mines as a thing of the past . The ancient workings, consisting of shafts and galleries for excavating the ore, and pans and other arrangements for extracting the metal, may still be seen . The mines are still worked at the present day by French and Greek companies, but mainly for lead, manganese and cadmium . The population of the modern town was 10,007 in 1907 . See E . Ardaillon, " Les Mines du Laurion dans 1'antiquite," No. lxxvii. of the Bibliotheque des ecales francaises d'Athenes et de Rome .