Positive Oxide And Sulphide Recoveries At Sugarloaf Peak Gold Project
TORONTO - Arizona Metals Corp. reported positive metallurgical testing results from its Sugarloaf Peak Gold Project in La Paz County, Arizona. Arizona Metals previously completed bottle-roll testing on two metallurgical holes (SP-20-01 and SP-20-02). The initial results from these tests achieved gold recoveries averaging 76% with oxide material recoveries as high as 95%. As a result of these initial results, the Company engaged SRK Consulting (Global) Limited to oversee metallurgical test work to develop a low-cost flow sheet to recover the gold.
The results of column testing of Sugarloaf oxide material achieved gold recoveries of up to 90%. Additional metallurgical testing was also completed with a focus on developing a conventional low-cost flowsheet to recover sulphide-hosted gold at Sugarloaf. Two sulphide flowsheets were considered for this test work: Whole-Ore-Leach (WOL) and bulk flotation followed by fine grinding of concentrate and leaching.
Four sulphide composite samples were prepared, ranging from 0.30 to 0.60 g/t gold and 2.2 to 5.3% sulfur. The test results indicated gold recoveries of up to 85%. Both flowsheet options were similar with overall final recoveries within 1% for all the Samples. Leaching kinetics for all four composite samples were fast, reaching maximum recovery at 24 hours. Comminution tests indicated a relatively soft material with SAG Circuit Specific Energy (SCSE) values of 7.8 kWh/t.
Mineralogy and diagnostic leach tests on the Samples indicate the majority of gold is present as free gold within sulphides, primarily pyrite. As the Samples tested demonstrated relatively soft material, it is likely that WOL will be the preferred processing method. The Company will conduct additional WOL leach tests to optimize grind size vs recovery, as well variability testing of different samples using the WOL flowsheet.
Sugarloaf hosts a tabular, open-pit type target that starts at surface. The project comprises 4,412 acres of unpatented BLM federal mining claims that are close to infrastructure including roads, gas, power, water, rail and labour. Recent drilling completed by Arizona Metals (SP-20-01) intersected 137 m grading 0.53g/t gold (including 90 m of 0.62 g/t gold) starting from surface, and 30 m of 0.90g/t gold, starting from 44 m. The Company intends to complete additional drilling in the future in order to confirm, and ideally expand, the historic resource of 1.5 million gold ounces. There are currently 26 drill pads permitted to carry out this work. A comprehensive drill program and budget is being formulated with the intention of commencing work when the gold resource capital markets improve.
Marc Pais, CEO, said, "The historic estimate at the Sugarloaf Peak Gold Project of 1.5 million ounces at 0.5 g/t gold was defined to a depth of only 70 metres. Testing has confirmed that oxide material near surface can achieve recoveries of up to 90% using conventional leaching. We believe there is also the potential for an underlying large sulphide deposit at depths below what was tested by historic drilling. Recent drilling by Arizona Metals encountered sulphide-hosted gold at depths down to 369 metres. The deposit is also open for expansion on strike, with the same geophysical signatures we see on the historic resource extending for more than double the strike length both to the northwest and southeast of the historic resource envelope. In addition to the excellent oxide recoveries, today's positive test results on the sulphide component of mineralization demonstrates the potential for a conventional low-cost flowsheet for sulphide material encountered below the historic resource. The Sugarloaf Peak Gold Project is fully-permitted for drilling, with 26 pads targeted for both infill and expansional drilling at depth and on strike. Drilling will be undertaken in due course to outline the size potential of the sulphide mineralization."