American Bonanza Sends Out First Shipment of Gold Bearing Concentrates

The American Bonanza Gold Corp. (TSX:BZA,OTCQX:ABGFF) 100% owned Copperstone gold mine in Arizona has placed onto transport its first shipment of gold bearing concentrates, consisting of 31.2 tons of concentrate grading an average of 22.8 ounces per ton of gold, containing an estimated 712 ounces of gold in concentrate.

As quoted in the press release:

The processing plant continues to perform well, as indicated by the consistent and low grade tailings assays, in the order of 0.06 ounces per ton gold during the two weeks of mid-February. Low gold grades in the tailings indicate that most of the gold being fed into the plant is being collected in the gravity and flotation circuits where high grade concentrates are being produced. The gold processing plant has been treating ore grade rock for a short time, and accordingly performance estimates are preliminary in nature.

During the two weeks of mid-February, overall gold recovery in the processing plant was estimated to be 85%, according to preliminary data. During February, the gold grade of ore delivered to the processing plant roughly doubled as compared to January (a partial month), and the tailings grade rose as a consequence. As the operators become more familiar with the plant and the Copperstone ores, Bonanza expects the processing plant to adapt more quickly to the changing grades, and achieve consistently low tailings grades. This would effectively increase the overall gold recovery. Additionally, optimization of the gravity circuit is aimed at further improving the gold recovery over the next several months.

Underground mine performance continues to improve. During 2012, the mine has been focused both on development mining to gain access to future ore bearing stopes, and mining ore from currently available stopes. Over a ten day operating cycle, excluding one day when the mine did not produce ore, the mine averaged 214 tons of ore per day, nearly half of the design mining rate of 450 tons per day of ore. Surface ore stockpiles currently contain approximately 2,700 tons of ore, which will allow the gold processing plant to continue increasing throughput as the mine tonnages increase to provide ore to the processing plant. Bonanza’s objective is to bring mine production up to design levels as the processing plant works through the surface stockpile, so that when the stockpile is drawn down, both the mine and the processing plant will be up to their 450 tons of ore per day target levels.

American Bonanza President & CEO, Brian Kirwin, said:

“Shipment of the first gold in concentrate represents another important milestone in the operation of the Copperstone gold mine. Performance of the mine and processing facility continues to steadily improve in every aspect. We at Bonanza are encouraged by continued improvement in performance, and look forward to bringing the Copperstone gold mine up to design throughput in the near future.”

Click here to read the American Bonanza Gold Corp. (TSX:BZA,OTCQX:ABGFF) press release