The WBL Tailings were created by the mining of primary clays from 1960 to 1974. The operator at that time was focused on the kaolin component from the primary clays and wasted the potassium feldspar (K-spar) and quartz fraction to the tails. Recognizing the tailings represented an excellent source of K-spar and quartz, in May 2010 I-Minerals commissioned SRK Consulting (USA) Inc. of Denver, Colorado to provide an estimate of the potential of the WBL Tailings resulting in an indicated resource of 509,000 short tons of recoverable feldspathic sand containing about 92,000 tons of K-spar (18% feldspar) and 214,000 tons of quartz (42% quartz) over an average thickness of about 17 feet.
A bulk sample of the WBL Tailings has been processed to yield a high quality K-spar product that has very low iron and other trace elements. Fire testing of the MC Feldspar in a comparison with a currently available K-spar product and a nepheline syenite product resulted in the MC K-feldspar button being whiter button than the button from the currently available K-feldspar (see photo in photo gallery).
With little further processing, the feldspathic sand can be readily used as filler in ceramic body applications given it fires white. Servicing this market simply requires excavation of unconsolidated K-spar and quartz bearing feldspathic sand and screening to remove undesirable constituents prior to being loaded. Additional grinding and other processing may be required by the end users.
Other market opportunities exist in sports field maintenance where the sand product can be used as a top dressing. These opportunities include the many golf courses in the general area of the Helmer-Bovill property.
I-Minerals has been granted a reclamation permit by the Idaho Department of Lands to mine up to 50,000 ton per annum of the feldspathic sand for a period of 10 years. Mining is limited to the June through October period. Initial production was achieved in October 2012.