Tag Archives: 3 Aces

Golden Predator, EnviroLeach hit on the right gold extraction and recovery formula

Environmental, Metallurgy, Mineral exploration, Mineral processing, Mineral project development, Mining services, Precious metals, , , , , , ,

Golden Predator Mining says tests have successfully confirmed that EnviroLeach Technologies’ environmentally friendly technology can effectively extract and recover more than 95% of the gold from sulphide concentrates produced at the 3 Aces gold project, in the Yukon of Canada.

The concentrate is produced using Golden Predator’s Secondary Recovery Unit (SRU™).

With this environmentally friendly technology confirmed in successive tests both in the EnviroLeach facility and at the Golden Predator bulk sample processing plant (pictured), the companies have initiated a larger material test run to process up to 5 t of gold-bearing sulphide concentrates to be completed onsite at Golden Predator’s plant in the Yukon, they said.

This testing follows an earlier agreement between the two companies to use EnviroLeach’s proprietary cyanide-free hydrometallurgical technology to extract gold from gravity concentrate produced at 3 Aces.

As part of this testing, a sample of gold-bearing sulphide concentrate recovered in 2018 was shipped from Golden Predator’s plant to the EnviroLeach facility in Surrey, British Columbia, in August of 2019.

Some 55.9 kg of the material was processed using EnviroLeach solution and 96.5% of contained gold was leached in six hours; and gold in solution was extracted by electrowinning and poured into a 91.3 g bar.

A sample of gold-bearing sulphide concentrate recovered in 2019 was also sent to and processed by EnviroLeach at the facility, with 30.4 kg of the material processed using EnviroLeach solution with 96.7% gold recovery in 29 hours; and gold in solution extracted by electrowinning in four hours and poured into a 77.8 g bar.

Following completion of test work in the EnviroLeach facility in Surrey, on-site testing was initiated to leach material at the plant during the week of September 23, 2019. This saw 121 kg of gold-bearing sulphide concentrates produced during 2019 processed in 21 hours with a 96.2% gold recovery; and electrowinning completed in 14 hours, with 255 g of gold recovered from the electrowinning cell and poured into a bar.

Janet Lee-Sheriff, Chief Executive Officer of Golden Predator, said: “Working with EnviroLeach provides us a unique opportunity to lead the way for safe and responsible new cyanide-free extraction methods in processing gold bearing concentrates which has immediate value on our 3 Aces project as well opening up other commercial opportunities.”

The Golden Predator-EnviroLeach working relationship has enabled the companies to successfully demonstrate the first “in the field” recovery of gold from gold-bearing sulphide concentrates, using EnviroLeach’s environmentally friendly formula and Golden Predator’s SRU processing equipment, according to the companies.

EnviroLeach cyanide-free tech to be tested on Golden Predator’s 3 Aces gold

Environmental, Metallurgy, Mineral processing, Mineral project development, Precious metals, Water management, , , ,

EnviroLeach Technologies and Golden Predator Mining have entered into an agreement that will see EnviroLeach’s proprietary cyanide-free hydrometallurgical technology extract gold from gravity concentrate produced at Golden Predator’s 3 Aces project in the Yukon of Canada.

This working relationship provides both companies with the first on-site bulk test of EnviroLeach’s new cyanide-free technology, they said.

Initial laboratory, pilot scale and production scale testing was successfully conducted at EnviroLeach’s facility in Surrey, British Columbia, prior to on-site testing at Golden Predator’s processing plant in the Yukon. All tests were conducted under the supervision of EnviroLeach and Golden Predator personnel with results to be released shortly, they said.

The initial 5 t bulk test will be conducted in phases and completed at the plant, they added.

Golden Predator operates the plant for the purposes of bulk sample testing of gold concentrate from its 3 Aces project. As part of its processing plant, Golden Predator developed a mobile batch recovery unit (Secondary Recovery Unit or SRU™) for the recovery of gold from its sulphide concentrate. Golden Predator intends to use the EnviroLeach proprietary cyanide-free technology in the SRU, it said.

Duane Nelson, President and Chief Executive Officer of EnviroLeach, said: “The gold recovery from Golden Predator’s arsenopyrite concentrate confirms the ability of our new eco-friendly formula to extract gold into solution from sulphide ores and recover it using conventional technologies.

“EnviroLeach is the only commercial-scale, economically viable and safe hydrometallurgical gold extraction process in the world. Our unique and eco-friendly process will change the way the world produces and recycles gold.”

Janet Lee-Sheriff, Chief Executive Officer of Golden Predator, added: “The plant and SRU are examples of the continuing ways that Golden Predator works to be innovative, testing new methods that have the ability to change how we operate at projects like 3 Aces.

“Working with EnviroLeach provides us a unique opportunity to lead the way for safe and responsible new cyanide-free extraction methods in processing gold bearing concentrates.”

The EnviroLeach process can effectively dissolve gold into aqueous solution with similar leach kinetics and economics to that of cyanide but is sustainable, safe and environmentally friendly, according to the company. This water-based process has a broad applicability spectrum and is effective on most gold ores and concentrates, the company said, potentially unlocking the value of many deposits located in environmentally sensitive areas that cannot be developed using current extraction methods.

Golden Predator’s test processing plant (pictured), the first of its kind in Yukon, Canada, commenced operations in 2016 providing increased metallurgical and geological understanding of its 3 Aces project. The plant is a relatively simple gravity circuit using a closed-circuit water system with no added chemicals due to the free-milling nature of 3 Aces gold.

The 50 t/d closed circuit plant recovers gold from #1 concentrates realising over 85% recovery of contained gold with doré bars sent to a commercial refinery for final processing. Golden Predator is currently testing EnviroLeach’s patent pending technology in it’s SRU for the extraction of gold from their #2 concentrates.

The 3 Aces Project is an orogenic gold project in southeast Yukon which provides the testing material for the processing plant. Golden Predator has to date focused exploration on a broad gold-in-soil anomaly, where numerous orogenic gold-bearing quartz veins have been discovered.

Golden Predator made an early decision to bulk sample at its 3 Aces project when it realised that much of the gold contained in its veins is high grade (not uncommonly over 30 g/t gold) and nuggety. The best way to determine the true gold value of a nuggety gold system is to conduct large scale bulk sampling which also allows Golden Predator the opportunity and ability to conduct on-site bulk metallurgical and processing tests.