Tantalite
Combining official production data for 1965–2013 with best estimates of older production (Puustinen, 2003), the main feldspar (+ quartz + in some cases small amounts of beryl, columbite, tantalite, etc.) ore-mining regions in Finland are ranked by Puustinen as follows:Kimito Island, southwest Finland: 5.82 Mt pegmatite (diverse quarries) and …