Canada Sc #10 (1857) – 6d Consort on Thick Paper Numeral Cancel XF Used w/Cert

6d reddish purple Consort Thick Fibrous Paper w/Numeral XF Used on very thick fibrous soft paper, exceptionally large balanced margins, centrally-struck four-ring “21” numeral cancel of Montreal, rich pleasing colour, likely one of the finest examples extant, extremely fine; with 1999 Royal Philatelic Society London and 2023 Greene Foundation certificates. A BEAUTIFUL AND CHOICE EXAMPLE OF THIS RARE PRINTING