Bidspirit auction | Soviet Union Stamps of 1924-40

Soviet Union Stamps of 1924-40 - 1935, Mikhail Kalinin, perforated (13¾) trial color proof of 10k in green, nicely centered, no gum (probably removed from a presentation card), VF and scarce, a common stamp of 10k in slate blue is included, Est. $800 -$1,200 , Sc. #575