Arizona Gold & Silver Inc (TSX-V:AZS) reported positive results from tests designed to extract gold from samples taken from its Philadelphia gold-silver property in Arizona.
These tests, known as agitation cyanide leach tests, involve using cyanide to dissolve gold from ore. The results showed that the gold could be efficiently and effectively extracted using this method, indicating that the material is highly suitable for this type of extraction process.
This success suggests that the gold at the Philadelphia property can be easily recovered using conventional mining and processing techniques, enhancing the project's potential profitability.
Tests conducted by McClelland Laboratories in Sparks, Nevada, demonstrated gold recoveries ranging from 90.6% to over 99.3% across all milled feed sizes. Faster leach kinetics and higher ultimate gold recoveries were observed at finer feed sizes.
Additionally, cyanide and lime consumption were low, averaging 1 kilogram per tonne for lime and less than 0.1 kilogram per tonne for cyanide.
Arizona Gold & Silver vice president exploration Greg Hahn told investors that the results represent “an important milestone for the project.”
“These excellent results demonstrate the ready amenability of the feed material to milling/cyanidation treatment at different feed sizes, and the potential for heap leaching,” Hahn said in a statement.
The tests involved four agitation leach (bottle roll) tests on each bulk sample, with feed sizes from 80% passing -425 microns to -106 microns, performed at a cyanide concentration of 1.0 gram per liter over 120 hours. Additional tests on -1.7mm feed size samples at varying cyanide concentrations for 72 hours indicated potential for heap leaching with gold recoveries of 72.7% to 73.6%.
Ongoing column tests on bulk samples at feed sizes of 80% -6.3mm (-1/4 inch) and larger, under leach for over 92 days, show nearly linear recovery curves, with smaller feed sizes demonstrating faster leaching rates. These tests will continue for at least 120 days or until gold extraction decreases significantly.