The mine investigated — Lövsvedsgruvan — is situated in the iron-ore formation of central Sweden. Figs 1 and 2 show the ore-body. The main field of investigation was the bottom 303 m level, which has been mapped. On this level there are several kinds of rocks: leptite, granitic leptite, iron-ore and skarn, all occurring as fragments in diorite. Granite and amphibolite are also present.