Traditional copper work in Mexico has its origins in the pre Hispanic period, mostly limited to the former Purépecha Empire in what are now the states of Michoacán and Jalisco. The reason for this was that this was the only area where copper could be found on the surface. After the Spanish conquest of the Aztec Empire, the Spanish took control of copper production, introducing European techniques but still needed indigenous labor. Copper work, like other crafts, was principally organized in Michoacán under Vasco de Quiroga. It is not known when the town of Santa Clara del Cobre came to specialize in the production of copper items, but it was well established by the mid 18th century. Copper extraction remained centered on Michoacán during the colonial period but most of the production gave out by the 19th century. After the Mexican Revolution, copper smiths of Santa Clara were limited to working with scrap metal making pots, plates, casseroles and other containers. Today, it remains home to hundreds of copper smiths which work in ways little changed from the colonial period and is home to the annual Feria del Cobre (Copper Fair) in August.