Paintings are usually sketched on the canvas before work begins, and sculptures are frequently planned using a maquette. These works-in-progress can be as sought after as (or even more sought after than) completed works by highly regarded artists because they help reveal the process of creating a work of art. Gian Lorenzo Bernini, a sculptor from the Baroque period, made his bozzetti (an Italian term for the prototype sculpture) from wax or baked terracotta to show those that had commissioned him how the final piece was intended to look. Eleven of these bozzetti were displayed in an exhibition at the Art Institute of Chicago in 2004. Some museums specialise in collections of maquettes, such as the Museo dei Bozzetti in Pietrasanta, Italy.