UNIC SAARGEBIET letter German occupied France dates 9.4 25.20 with 3 stamps

Letter with 3 stamps Cancelled postage stamp printed by Germany, Saarland, that shows "Miner at work " 5 centime and "Old bridge" - German territory South-east of Luxembourg- Occupied by France under League of Nations control from 1920 to 1935. Sended from St. JOHANN Well for collection and exhibition !