The most precious. You're not far either from the stations Madeleine, Tuileries or Pyramides, but the best (and easiest) is to walk from Place de l'Opera through Rue de la Paix straight to Place Vendôme, the jewellers square. You can admire the last creations from Boucheron, Van Cleef and Arpels, and so many more. In the middle of the square is a nice column made from the melted guns of the enemy. This is an other of Napoleon's ideas!