Abstract: A cyclic, two-stage process is disclosed for pyrometallurgical recovery of copper as a high-grade matte from molten slag material containing both dissolved and/or entrained copper values. A charge of the copper-bearing slag material is treated in the first stage of the process with a hydrocarbonaceous or hydrogenous reductant in a rotary furnace, such as a top-blown rotary reactor, rotating at at least about 10 rpm, to form a high-grade copper matte phase and a slag phase of reduced copper content. The rotation of the reactor is discontinued and the high-grade copper matte phase separates from the slag phase and is recovered from the reactor. The reactor containing the remaining slag of reduced copper content is again rotated at about 10 rpm, and iron sulfide, e.g. pyrite, is added in the second stage of the process to the slag in the rotating reactor to provide a low-grade matte phase which literally "washes out" most of the remaining copper contained in the slag.