Aug 19 2010
Rare Element Resources Ltd. (TSX-V: RES) is pleased to announce progress toward defining a commercial process for rare-earth-element (REE) concentration from oxide samples collected on the Company's 100%-owned Bear Lodge property, Wyoming, USA.
The favorable metallurgical test results on a large sample of near-surface high-grade oxide mineralization indicate the following:
- With scrubbing/attritioning in water, a preconcentrate is produced with a recovery of approximately 90% and a grade up to 20% rare-earth oxide (REO); the REO resides in the finer fractions (-100 to- 500 mesh).
- Hydrochloric acid leaching of the preconcentrates in an agitation leach system gives a recovery of about 80 to 85% of the total REO from the original mineralized material in the same general proportions as the original REO distribution.
- Additional testing is being conducted to optimize the processing methods.
Metallurgical testwork is being conducted at Mountain States R&D International, Inc. (MSRDI) of Vail, Arizona. Additional tests of REE extraction and separation are underway at Intellimet LLC of Missoula, Montana. Plans for confirmatory testing by NAGROM of Perth, Australia and by ANSTO of Sydney, Australia are being formulated. Bulk sampling of oxide mineralization from large diameter drill core and from surface trenches will take place this fall. The bulk sample will be processed in a pilot plant test in 2011 as part of a planned prefeasibility study.
The metallurgical testing is ongoing on oxide samples from an NI 43-101-compliant inferred resource of oxide mineralization consisting of 8.0 million tons averaging 3.6% REO. Nearly all of this material is sufficiently close to the surface for projected mining by open pit methods. The oxide resource is part of a larger total inferred resource estimated at 17.5 million tons averaging 3.5% REO, using a 1.5% REO cutoff grade (see news release dated May 26, 2010). The oxide zone mineralization extends from surface to depths of 400 to 500 feet. Excellent exploration potential for expansion of the oxide zone is being tested currently by a program of step-out drilling, while in-fill drilling is directed at an upgrade of the resource category.
The current testing program conducted on this oxide mineralization is designed to take advantage of the unique mode of mineral occurrence of the REE mineralization. The mineralization is characterized by fine-grained REE minerals that variably adhere to the surfaces of the coarser gangue (non-REE-bearing) minerals. The REE minerals in oxide mineralization from the resource area are nearly all from the bastnasite group-listed in decreasing order of abundance: synchysite, parisite, and bastnasite, with generally minor monazite.