LONDON.- Pieces by the most influential British gold and silversmith of the last century, Gerald Benney, are for sale in the Silver Auction (including post-war silver) at Bonhams Knightsbridge on 25 May. It follows the highly successful sale of Benney’s work last December which made more than £150,000. The star lot in May’s sale is a silver-gilt and enamelled teapot, from 1991, estimated at between £4,000-6,000. This is the only known example to have appeared at auction. The teapot features Benney’s distinctive ‘Bark Finish’ – the surface texturing of silver which became his signature and influenced contemporary silver design for almost two decades. He discovered this by accident when he mistakenly used a hammer with a damaged head and liked the effect it produced. Other pieces in the sale include a silver and gold box (£3,000-4,000); eight silver and enamelled beakers, (£3,500-5,000; a pair of s