The formations of the Shinkolobwe ore deposit form a spur of the Mine Series wedged into a fold-fault. Uranium minerals, and associated cobalt, silver, nickel, bismuth and arsenic, occur as massive sulfide ore in veinlets along fractures, joints, and minor faults within the Katanga synclinorium. Uraninite mineralization occurred 630 Ma, when uraniferous solutions percolated into the dolomitic shales of the Precambrian Mine Series (Serie des Mines), under the Roche Argilotalqueuse (R.A.T.) nappe. The Mine Series is a Schist-Dolomite System postulated to be in the Roan System. This schistose-dolomite appears structurally between two contacts of the Kundelungu System, the Middle Kundelungu and the Lower Kundelungu, of the Katanga Group. The Lower and Upper Kundelungu form a double syncline, the northern limb of which overlies the Shinkolobwe Fault. These structural complexities aside, the Katanga stratigraphic column consists, top to bottom, of the Precambrian Kundelungu System (Upper, Middle and Lower), the Grand Congomerate and Mwashya Systems, the Schist-Dolomite System (Roan System-Mine Series of R.G.S., C.M.N., S.D., R.S.C., R.S.F., D. Strat., R.A.T. Gr., and R.A.T.) and the Kibara Group.