The smelting and refining of Tin began operations on 26 March 1996, being the first foundry in the world to use submerged (entry) nozzle technology for the processing of Tin concentrates. This modern plant processes concentrates from the San Rafael mine by applying Sirosmelt lance technology, which consists of mixing Tin concentrate with limestone, iron ore and anthracite. This mixture melts at high temperatures in a cylindrical oven with the upright nozzle submerged until a crude metal of a purity of approximately 98% of Tin is obtained.