Lot
562 
Mexico, Airmail, 1929, 25c dark green & gray brown, perf 14, trial color proof, full o.g., strong colors, Very Fine, one of the rarest "issued" proofs; with 1978 M.E.P.S.I. certificate. Scott No. C3 var. Sanabria No. 5 Estimate $750 - 1,000.
On May 3, 1929, certain proofs or essays were sold at the post office in Mexico D.F. There were seven varieties in colors, perf and imperf, and a total of 225 examples all in toll were sold.
Realized: $750