A total amount of 1–1.5 Mt of country rock and gangue will be mined during the whole lithium mining operation from the Läntä deposit. Part of this rock will be used to fill the underground mining space, and the rest will be sold as crushed stone and macadam to the construction and earthworks sites in the surrounding area.   

The country rock consists of greywacke schist, which can be crushed into second and third class macadam and crushed stone. It can be used for both sub-base and base course in earthworks. It is also suitable for the production of concrete, as well as for heavy duty road pavement. The crushed stone and macadam will be marketed on a regional basis.