 In 1910 Mackennal designed the Coronation Medal for King George V and also won the important commission for the obverse design (the monarch's head) of the new coinage needed for the new reign from 1911, from which he developed the new design for the King's head on British postage stamps.This is certainly his most enduring design.His initials, B.M., can be seen on the truncation of the King's neck on the obverse of all British coins of George V. His next important work was the memorial to Thomas Gainsborough at Sudbury, which was followed by the memorial tomb of King Edward VII at St. George's Chapel, Windsor.