A circular approach creates value from residual products, whether they come from our own operations or other industries. This means that we can now offer a wide range of by-products. These, in turn, fulfill important functions in society. Our by-products come primarily from the Rönnskär and Harjavalta smelters. At Rönnskär we extract copper sulfate, zinc clinker, and iron sand from slag from copper production. At Harjavalta we extract copper sulfate and copper telluride. These are just a few examples of the further processing of materials at our smelters.