December 4, 2017. Thompson Falls, Montana. United States Antimony Corporation (“USAC”, NYSE American “UAMY”) reported that SEMARNAT (the equivalent of the U.S. EPA) has issued USAMSA (a wholly owned subsidiary of USAC) the permit for a cyanide leach plant for the Puerto Blanco mill in Guanajuato, Mexico.
The plant is designed to recover gold and silver from the pilot flotation mill tailings of the Los Juarez gold-silver-antimony deposit in Queretaro, Mexico. The deposit is 3.5 kilometers in length and over 1 kilometer in width. It has all the signature elements of the Carlin gold mine and the Robert’s Mountain over-thrust belt in Nevada. The deposit has been owned by two major mining Companies but has never gone into production due to the complex metallurgy. USAC has solved the metallurgical problem with the floatation product by adding an alkaline leach circuit. A second issue was that the mill only recovered 30 to 50% of the gold and 60 to 80% of the silver in the flotation concentrate. Test work showed that these values could be recovered by a cyanide leach of the mill tailings. USAC has finally gotten the permit for the cyanide leach after many years. Construction of the leach circuit has commenced. Initial projects will include a plastic liner for the tailings pond and construction of the leach plant building. In Montana, construction of leach plant equipment is underway
The Los Juarez deposit is mined by open pit, bulk- mineable methods. The estimated recovery of the values after the caustic leach of the flotation concentrates and the cyanide leach of the tailings is as follows (3.09 grams/metric ton gold equivalent at current prices):
Metal | Assay | Recovery | Value | Value /mt |
Gold | 0.035 opmt | 90% | $1,286/oz | $40.51 |
Silver | 3.27 opmt | 90% | $17.01/oz | $50.06 |
Antimony | 0.652% | 70% | $3.80/lb | $38.11 |
Total |
|
|
| $128.68 |
A major raw materials supply contract was renewed on November 1, 2017 until the end of 2018. Our processing cost allowance was increased by 34.8% and our percentage of the profit was increased by 2%. .
At the beginning of November 2017, the average Rotterdam price of Grade I antimony metal per metric ton was $8025.00 ($3.640 per pound), and by the end of November, the price had increased to $8150.00 ($3.696 per pound) approximately a 1.5% increase. The total non North American production in October was 44.4% and that for November was 41.8%.
CEO John Lawrence said “We are excited about receiving the cyanide leach permit for the Los Juarez gold-silver-antimony deposit. The pilot plant will establish major gold and silver production for USAC and pave the way for the mill expansion. We intend to fund the construction of the cyanide leach plant from cash flow and to ramp up pilot production in 2018. We continue to evaluate several financial opportunities presented to the Company that do not involve dilution of any kind. We will keep you advised on these opportunities.”
Original Article: http://usantimony.com/2017_newsroom.htm#U. S. ANTIMONY REPORTS APPROVAL OF LOS JUAREZ LEACH PLANT PERMIT