Great Britain 1856 6d deep mauve plate proof, SG69varGreat Britain 1856 6d Deep Mauve Plate Proof, SG69var A superb and very fine imperforate plate proof of the 6d Queen Victoria issue, printed in deep mauve on thin white paper. A striking example enhanced by a neatly struck black experimental circular date stamp (CDS) cancellation dated 'AP. 9. 1856'. Proofs of this nature were not intended for general circulation, making surviving examples exceptionally scarce. A rare and desirable piece from the