A simple diamond and sapphire engagement ring that Napoleon Bonaparte offered to his first wife Josephine goes on auction near Paris next month, the auction house Osenat said on Friday. The gold ring is topped by two pear-shaped stones and is estimated to fetch up to 12,000 euros ($16,000) at the March 24 auction in Fontainebleau, south of Paris. "At the time, Napoleon had very little money. The ring is a very ordinary one," Jean-Christophe Chataignier, who head Osenat's department of historical objects, told AFP.