Lot 5, Canada twelve penny black plate proof with diagonal SPECIMEN overprint May 23, 2024 by Sparks Auctions Lot 5 Canada #3Pii 12d Queen Victoria Plate Proof in Black, with Diagonal SPECIMEN Overprint in Carmine, on India paper, with four full margins, very fresh and very fine. Rsv $4,000. Unitrade CV$6,000.