Brazil's share of the world tin cas-siterite production increased from 3 per cent in 1980 to almost 22 per cent in 1989. Pitinga and Bom Fu-turo, two deposits discovered in 1979 and 1987 respectively, together increased the production capacity of Brazil by over 700 per cent. The superior geological conditions and the favorable economics of these deposits have been the dominant and necessary factors behind the soar in Brazilian tin cassiterite mining. However, the International Tin Council's market interventions from 1976 and onwards as well as domestic governmental support have also been crucial for the development described.