North Bay Resources Inc. (OTC:NBRI) has unveiled the results of gravity recovery testing of run-of-mine ore from the Mt. Vernon Gold Mine in California, which included the first discovery of platinum at the site. The company said run-of-mine ore from the main channel at the mine was first crushed to a fine powder using a ball mill, achieving a size of minus 60 mesh.
It was then processed on a gravity recovery table, producing two concentrated streams with gold concentrated approximately 10x.
Sample #C1 MV Cons returned 11.95 ounces per ton of gold, 17.54 ounces per ton of platinum, and 7.79 ounces per ton of silver and Sample #C2 MV Cons returned 11.38 ounces per ton of gold, 2.20 ounces per ton of platinum, and 5.59 ounces per ton of silver.
Notably, this is the first known discovery of platinum at Mt. Vernon with the region, in general, not known for platinum.
North Bay Resources said it is conducting additional studies on the deposit to better understand the relationship between gold and platinum, aiming to increase the ore’s per-ton value by as much as 50% in certain concentrate streams.
A recoverable gold to platinum ratio of up to 1:1.5 can be achieved through basic grind and gravity separation, recent results show.
It said that while metallurgical testing is ongoing, initial results have confirmed the viability of gold, platinum, and silver extraction at the mine using a basic grind and gravity recovery circuit, which is essentially identical to the grind and gravity recovery circuit at North Bay Resources’ 100 ton-per day Bishop Gold Mill.
Testing of the on-site metals furnace and related equipment at the mill has commenced to upgrade concentrate into and pour Dore bars and produce platinum buttons to be shipped to a metals refinery in Reno, Nevada.
Meanwhile, a second round of Summer Exploration at North Bay Resources’ Murex copper-gold project is ongoing.
The company has identified a high-grade copper trend running northeast-southwest at the surface and has confirmed the location of the known copper-gold deposit originally developed by Noranda (now Glencore) in the 1980s. Additional sampling is in progress, and a thorough re-evaluation of the property will take place after this phase.
At the company’s Fran Gold Joint Venture in British Columbia, property-wide exploration has been completed and a shipment of five 50-pound samples has been received at the Bishop Gold Mill for evaluation and testing.
The samples include ore from the main Bullion Alley zone, where a consistent ore grade of 0.5 ounces per ton has been established over a large area.