The lithium deposit in Länttä contains an average of 230 ppm of columbite. Columbite occurs as elongated crystals of less than 1 mm. In production it can be easily separated by the gravitational method.  

The columbite concentrate is a by-product that provides added value, containing tantalum and niobium. The value of the concentrate is usually determined by the equivalent content of tantalum pentoxide (Ta2O5), but in Länttä the value of niobium pentoxide (Nb2O5) in the concentrate is significant as well. On average, the Länttä deposit contains 68 ppm of Ta2O5 and 117 ppm of Nb2O5.  

Tantalum is mainly used in the manufacture of tantalum capacitors within the electronics industry. Tantalum is produced in Australia, Canada and Central Africa, mainly in Congo and Rwanda.