Mexico, 1861, 4r black on yellow, half used as 2r, Guadalajara. Upper left half of stamp tied by blue Guadalajara cds (Schatzkes 297) on 1861 folded letter to Zacatecas, Very Fine, this date stamp cancel was only used in blue for a few weeks in 1861; signed Calves, with 2007 Jaretzky, 2008 P. Scheller and 2010 MEPSI certificates. Scott No. 9a  Estimate $300 - 400. $0 (Image)