I believe the set is relatively new. It is not crazing you see in the photograph, but rather the distinction way they colored the shakers.
If not marked "Gaudi" on the bottoms, these unusually shaped salt and pepper shakers would be rather difficult to most collectors to determine their significance. They depict the famous chimneys that sit on top of one of Gaudi's famous architectural creations - the Casa Mila.
Casa Milà, popularly known as La Pedrera "the stone quarry" in reference to its unconventional rough-hewn appearance, is a Modernista building in Barcelona, Catalonia, Spain. It was the last private residence designed by architect Antoni Gaudí and was built between 1906 and 1912.