The Redox process utilizes nitric acid at a temperature of approximately 200 degrees C to oxidize sulfide minerals, releasing gold for recovery by conventional methods. The primary advantages of the Redox process are short retention time, less than 10 minutes, and, in the case of arsenic-bearing feeds, production of a stable ferric arsenate residue. These advantages lead to low capital and operating costs. The process is difficult to simulate on a batch basis because of the short retention time and kinetics variation in a batch reactor Bakyrchik concentrate has been treated in a continuous 15 kg/h pilot facility over a three month period. The continuous plant allows for recycle of nitric acid, which is regenerated within the Redox reactor The objectives of the pilot campaign were to optimize process parameters and prove the effectiveness of Redox for treatment of the Bakyrchik concentrate.