Atlanta Gold reports that further gold recovery process testing by Knife River Corp (KRC) on material from the company’s Atlanta project, in Idaho, has achieved higher recovery rates by reducing the grain size of the feed material to liberate gold and sulphides from unwanted gangue material. The process by which KRC reduces the size, but without grinding, is its own new proprietary technical application that is both cost effective and energy efficient. Atlanta Gold has been working this year with KRC on ways to improve the gravity system’s mineral recovery on material obtained in a 107-t bulk sample, which was completed in August 2012.
The first testing of the pilot gravity recovery plant’s process provided anticipated results that free gold could be separated but gold attached to gangue material could not be easily recovered. Additional testing had determined that substantial size reduction would be required to liberate additional gold and minerals from unwanted gangue.
KRC embarked on an innovative method to achieve required size reduction without grinding to liberate gold and sulphides from the gangue materials. As material size is reduced, recovery percentages have increased.
Atlanta Gold’s President and CEO Wm. Ernest Simmons said, KRC’s “proprietary technical application that markedly reduces the feed grain size to the gravity recovery process is a significant step to advancing the Atlanta gold-silver project and could lead to a low cost gravity recovery system in the near future. Our next larger bulk sample will provide the data needed to define the final production flowsheet.”
“The objective for a 100:1 ratio of feed to concentrate with acceptable recovery rates is becoming a reality,” added Simmons, “and the metallurgical testing of the gravity recovery process will continue.” Detailed analysis of all samples required for a metallurgical balance of tested recoveries in future tests will be performed by a certified NI43-101 compliant laboratory.
Atlanta Gold holds through its 100% owned subsidiary, Atlanta Gold Corp, leases, options or ownership interests in its Atlanta properties which comprise approximately 8.74 km2 located 90 air km east of Boise, in Elmore County, Idaho. A long history of mining makes Atlanta very suitable for development of new mining projects. The company is focused on advancing its core asset, Atlanta, towards mine development and production.
