Casa Masson was a watch store in Rio Janeiro. Founded in 1871, in Porto Alegre, by the Rio Grande do Sul watchmaker Reynaldo Geyer and the Rio jeweler Leopoldo Masson, the company was initially called Pêndula Misteriosa. Years later, when his Rio partner returned to Rio de Janeiro, the businessman from Rio Grande do Sul decided to pay tribute to his friend and changed the store’s name to Masson. A visionary, committed to offering the best merchandise of the time, Geyer faced long ship journeys to Europe, from where he brought watches and other items that stood out in retail, making jewelry and optics a national reference.