cape verde has few natural resources. only five of the ten main islands (santiago, santo antão, são nicolau, fogo, and brava) normally support significant agricultural production, and over 90% of all food consumed in cape verde is imported. mineral resources include salt, pozzolana (a volcanic rock used in cement production), and limestone. its small number of wineries making portuguese-style wines have traditionally focused on the domestic market, but have recently met with some international acclaim. a number of wine tours of cape verde's various microclimates began to be offered in spring 2010.