South Sea Baroque Pearl 'Koala' Brooch, by Buzzanca. Photo courtesy Tiancheng International Auctioneer Limited

Modelled as a koala holding a tree branch, the head and body set with baroque-shaped South Sea cultured pearls, to diamond-set ears and limbs, the nose and eyes accented by black diamonds, highlighted by tsavorite garnet- and diamond-set tree branch. Cultured pearls measuring approximately 21.00 to 19.50mm. Mounted in 18 karat white gold. Signed Buzzanca. Estimate US$13,000 - 20,000

Tiancheng International Auctioneer Limited. SPRING AUCTION 2013 JEWELLERY AND JADEITE. 15 Jun · 3 pm. Hong Kong Headquarters 30/F Bank of China Tower 1 Garden Road, Central Hong Kong http://www.tianchengauction.com/