The Rompas Prospect, Peräpohja Schist Belt, Northern Finland

The Rompas prospect in the Ylitornio municipality is one of the most exciting recent discoveries in Finland. Spectacular bonanza grades, with abundant visible gold in association with uraninite, are hosted within deformed dolomite–calc-silicate–quartz veins in metabasalts along a 6-km-long ridgeline. The highest gold grades are associated with texturally late, sulfur-bearing pyrobitumen inferred to have formed at least 150° cooler than peak metamorphic conditions, approximately 150 million years after the crystallization of the vein-hosted uraninite.