The change of contract for the production of stamped postal supplies caused a need for new, regular postage stamps. The new contractors started work on them as soon as they finished the Diamond Jubilee Issue. As a model to work from, the engravers used a photographic portrait of Her Majesty taken at the time of her Diamond Jubilee, and approved and signed by her. Realistic maple leaves decorated all four corners of the stamps. For this reason, stamp collectors refer to them as the Maple Leaves Issue. In a circular letter dated 25th October, 1897, the Department instructed postmasters to avoid selling the new stamps until they had sold corresponding values in the older issue. The result was that the issuance of the maple-leaf stamps in various denominations spread over a period of three months from November 1897, until January, 1898. Portrait of Her Majesty Queen Victoria, from a photograph by Messrs. W. & D. Downey, of London, England, taken in 1897 for the occasion of her Diamond Jubilee.