Vista Gold giving microbes a shot at Hycroft

Vancouver – The dormant heap leach pads at Vista Gold’s (VGZ-T) wholly owned Hycroft Mine still contain an estimated 600,000 oz. of gold, Pintail Environmental Solutions thinks it can get some of them out using microbes.

Hycroft, located in northwestern Nevada, was an open pit, heap leach gold producer from 1987 until 1998, when it was placed on care and maintenance. Over the eleven years, about 1.1 million oz. of gold was produced from two deposits. Small amounts of gold are still recovered from recirculating the heap pad solutions.

The heaps from the operation still have an estimated 600,000 oz. of gold contained, albeit at very low grades. The task is to find a method to liberate this gold from the processed ore, in place and at low cost.

Enter Pintail Environmental, who’ve been developing microbial leaching technologies over the last 17 years. Bacteria are utilized to enhance and accelerate gold recovery by solution leaching.

Vista Gold and Pintail will evaluate the process over the next year and, upon meeting specific milestones, enter into a joint venture whereby Pintail will earn a 50% interest in a commercial operation producing gold from the heaps. Pintail must demonstrate, at their cost, gold recovery with total costs below one-half of the prevailing market price.

Hycroft presently has a measured and indicated hardrock resource of 38 million tonnes grading 0.67 grams gold per tonne.

Colorado-based Vista Gold has eleven advanced stage and past producing gold projects in Nevada, California, Idaho, Mexico and Bolivia.

As of the latest report, the company has 15.5 million shares outstanding.