(FC18B//22B) Filled Cheese, Series of 1961, Set of Six in Blocks of Four, unused, all are Very Fine, includes: FC18B, 18cB, 19-20B, 21A, 22B, this set includes the rare 5c value (only 32 exist of this stamp), the internet retail for this set of blocks is $4,000.00, (ENV 3,000-3,500), EX: Smithsonian (Image)

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