A 1943 5l pro-assistance Aegean vertical pair is the headline lot of Spink's sale of the Assab collection of Italian colonies in Geneva on January 31.
The lot is expected to make up to $35,560.
The stamps were issued during the Axis occupation of the Aegean Islands in the early 1940s. Following Mussolini's ousting in 1943, the Germans removed and executed many of the local Italian administrators.
However, they left the Italians in control of other aspects of governance, including the postal service. The majority of stamps issued in the region between 1943 and 1945 are Italian, overprinted with "pro Assistenza Egeo".
Only 20 or so have made it to the present day, the majority of which are in poor condition. Spink describes the lot as the most important rarity of the Aegean Islands.
A Tripolitania 1926 blue is another highlight, with a valuation of $14,224.
The stamp is the most valuable ever issued in the region, which is now part of Libya. It was formerly part of the Ottoman Empire and covered the region around the coastal city of Tripoli.
Italy captured the small state in 1911, during the Italo-Turkish war.
The lot is printed "Segnatasse per Vaglia" or "postage by money order".
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