GB QV 1840 SG1 1d 'The Penny Blue' MB Fine Used 1844 cancel Very Rare cv £75000

A very rare 1d Penny Blue. Fine Used. Has 3 margins. No apparent faults. Something for the specialist and investor alike. 
1840 1d Blue 'The Penny Blue'  Used example lettered MB cancelled by type 1844 Black cancel. 
Shaved at right, clearly showing 'One Penny' these trials were printed by Rowland Hill in three colours. Red-Brown, Full Deep Blue, Prussian Blue as he wished to see the chosen colour of the 1d in sheet form he also wished to make a decision of the 2d. He chose the Full Deep Blue shade. Some of 1d Blue proofs reached the public and were Used for postage like this example. Cv £75000
An important piece of philatelic history, and a fabulous addition to anyone's portfolio.