Positive Results At the Pan Project In Nevada

 

DENVER, CO - Midway Gold Corp. reported positive preliminary results from metallurgical test work on run-of mine (ROM) bulk samples at Pan. Observed gold recoveries of 92% after 58 days indicate gold recovery of the South Pan ore is not sensitive to crush size. These metallurgical results suggest the South Pan ore can be processed with ROM leaching and that a crusher installation and spend at Pan can be deferred for at least 18 to 24 months.

Ken Brunk, President and CEO said, We are very excited by these new ROM test results. We saw indications in the 2010 pre-feasibility and 2011 feasibility column testing of South Pan ores that gold recovery seemed insensitive to crush size. However, due to permitting constraints we were unable to begin comprehensive ROM test work. Therefore, we elected to include crushers in the initial project, as we will need them for the North Pit ore regardless of South Pit design factors.

The company has continued to permit and test bulk samples of larger and larger particle size with favorable results. Our permitting team obtained permission from the BLM to conduct a trial blast in July at South Pan from which we could obtain true ROM ore for testing. Representative samples of the blasted ore were sent to Kappes-Cassidy & Associates (KCA) laboratories in Reno for leaching in large columns to simulate a ROM leaching operation. The duplicate 4 feet diameter columns are stacked with approximately 20,000 pounds of ROM ore each to a height of 15 feet and have already resulted in a gold recovery of 92% at 58 days. These excellent leaching results and leach kinetics are due to the fact that the rock is porous and permeable. In other words, the rock readily allows the leach solution to flow through the ore and to easily dissolve the gold.

The results of the large column tests lead the project team and management to conclude that ROM leaching is a viable option for South Pan. The excellent extraction of gold from the large-scale bulk sample also supports retaining the 85% recovery that is now confirmed by all the detailed test work to date. The size analysis of the large column test feed material is consistent with, and perhaps a bit coarser, than that from my experience with other ROM leaches on Carlin style formations. Midway will work with these large column results and use them to further refine our Pan project. Continued optimization of the mine plan will occur to ultimately dictate when the crushers will be needed.