KÖNIGSHÜTTE, German Empire postal stationery card 10 Pfg carmine-red Germania 1917 with added 5 Pfg dark green vertical pair and two singles Steelworks and Dove of Peace 1920 to Erfurt, double-circle KÖNIGSHÜTTE 7 1 21 * (OBERSCHL) d (OS handbook No. 157.5), rare cancel, Germania stationery technically prohibited but not challenged by postal administration, green shade on two stamps grading into green-olive (rainbow printing), age and use marks typical of period