1924 10k on 5r green, basic stamp wide "5" variety, light cds, v.f., signed Mikulski, etc., cat. $700 (Cat No. C7a) (Image)

Cat. $700, Est.$250

1924 15k on 1r brown, surcharge inverted, l.h., v.f., with handstamped guarantee mark, v.f., cat. $1400 (Cat No. C8a) (Image)

Cat. $1400, Est.$1,500

1924 20k on 10r carmine, surcharge inverted, Moscow cds, v.f., signed Mikulski, Dr.P.Jemchouhin, rare and undercatalogued variety, cat. $2500 (Cat No. C9a) (Image)

Cat. $2500, Est.$1,500

1930 Zeppelin 40k and 80k imperforate singles, h.r., the latter creased at top margin, signed Bartels, the latter Goznak handstamp, v.f., with Dr.Leupold certificates, cat. $3300 (Cat No. C12b-13b) (Image)

Cat. $3300, Est.$1,500

1931 50k violet brown, imperforate trial color proof on gummed stamp paper, large margins all around, l.h., v.f. A significant Soviet and Air Post rarity, only 24 (!) recorded, this one being position 15 (indicated in pencil), with "D" Postal Museum handstamp on back, 2016 Buchsbayew certificate (Sanabria 40) (Liapine 334P1) (Cat No. C18var) (Image)

Est.$5,000

1931 50k violet brown, imperforate trial color proof on stamp paper, large margins all around, canceled TULA, v.f. A significant Soviet and Air Post rarity, only 24 (!) recorded, this one being position 2 (indicated in pencil), with "D" Postal Museum handstamp on back, 2016 Buchsbayew certificate (Sanabria 40) (Liapine 334P1) (Cat No. C18var) (Image)

Est.$5,000

1931 50k gray blue (error), block of four, n.h., well centered, v.f., with 2010 Raritan guarantee. A rare multiple (Cat No. C23a) (Image)

Est.$7,500

1931 50k gray blue (error), used in combination with additional 80k franking on registered cover from Kharkov (4.12.40) to Germany, redirected on arrival from Soltau to Heligoland, with transit and arrival markings, censored and resealed by German Wehrmacht label on back, fine and extraordinary usage of the celebrated "Ospitka" color error on cover to the Third Reich (six months later Germany invaded the Soviet Union) (Cat No. C23a) (Image)

Est.$5,000

1932 Polar Year, set of two used on cover from Leningrad (11 Aug 39) to USA, fine-v.f., scarce commercial usage on one cover (Cat No. C34-35) (Image)

Est.$150

1934 Civil Aviation Issue, with and without watermark, n.h., minor gum skips as often, fine-v.f. sets, cat. $1220 (Cat No. C40-49) (Image)

Cat. $1220, Est.$250

1934 5k violet brown, perf. 14, n.h., v.f., signed Diena, etc., cat. $275 (Cat No. C50a) (Image)

Cat. $275, Est.$150

1935 Moscow-San Francisco 1r on 10k dark brown (Levanevsky), two copies, one lower case Cyrillic "f", l.h., v.f., signed Goznak, Diena, etc., cat. $2225 (Cat No. C68,68b) (Image)

Cat. $2225, Est.$750

1935 Moscow-San Francisco surcharge, lower case "f", used, v.f., signed Goznak, etc., cat. $1450 (Cat No. C68b) (Image)

Cat. $1450, Est.$500

1944 Memorial to the Soviet Balloonists who on 30th January reached the height of 22,000 meters", 50k green (Vasenko), 50k ultramarine (Fedosenko) and 50k gray green (Usyskin), imperforate trial color essays in unissued colors and denominations, each mounted on card, with handwritten technical inscriptions, value with penciled line and official handstamp and signatures on back, archival punches through last two, with 2019 Liapine certificates (Cat No. C77-79P) (Image)

Est.$15,000