Ceylon 1919 KGV 6c Die Proof, Single Plates, Before Striking

1912-25 DIE PROOF in black for KGV keyplate issue 6c (of 1919) from single plate (SG 305) complete design on glazed card marked BEFORE STRIKING and dated "27.11.18" with initials in manuscript. An exceedingly elusive state (after striking) of a scarce single plate die proof.