1848 20k Dark Blue envelope, broad tail, 1st watermark inverted, from the first printing of the 1848 issue, pen cross obliteration, at back manuscript departure annotation TVER 8.6.50 and boxed VORONEZH, plus POLUCHENO dated 11.6.50, backflap slightly strengthened by hinges, rare early stationery, cert. Mikulski, unpriced used by Lobachevsky or Standart