(IDEX Online) - A one-off Tiffany "Bird on A Rock" pendant watch is to feature in the Only Watch charity auction to raise funds for Duchenne Muscular Dystrophy.The watch case features a faceted aquamarine crystal of over 34 carats, and a dial set with 461 snow-set diamonds of over 1 total carat. It has an estimate of $390,000 to $556,000 (CHF 350,000 - 500,000).The bird is fashioned from platinum and yellow gold, with over three carats of round brilliant diamonds and pink sapphires for eyes.It recalls the iconic brooch Jean Schlumberger created for Tiffany & Co. in 1965.The watch is one of 62 lots that will be offered for sale by Christie's on 5 November in Geneva.The Only Watch auction started in 2005 and takes place every two years, attracting unique timepieces from the world's leading watchmakers.Pic courtesy Tiffany & Co