Lot 712, France 1850 one franc dark carmine Cérès used block of four

Lot 712 France #9c 1850 1fr dark carmine Cérès Imperforate, a used block of four, with “grille sand fin” cancels, large margins on three sides close to just in at left. Signed on back by Aimé Brun. This is a rare block of four, cataloguing €17,750 in the Maury / Spink catalogue and €16,500 in Yvert & Tellier. Rsv. Scott CV U$15,000.