Project: Kings Valley, Nevada
Chevron Resources began exploration for uranium in Nevada in the McDermitt Caldera area in 1975. In 1977 the U.S. Geological Survey alerted Chevron to the presence of anomalous concentrations of lithium associated with volcaniclastic moat sediments within the caldera. Based on the information from the USGS, Chevron analyzed drill cuttings from rotary percussion drill holes drilled in 1977 in the moat sediments for lithium. One hundred and forty feet of hole number MJB-7-4 averaged 0.278% Li; eighty five feet of MJB-7-5 averaged 0.236% Li. These results confirmed the presence of significant lithium hosted by a massive, green claystone within the moat sediment section.
In 1979 as Chevron continued evaluating the uranium resource, 34 rotary percussion holes were drilled to evaluate selected tailings disposal sites for anticipated uranium production. Those holes were drilled to test the thickness of the clays, to obtain samples of the clay for engineering analysis and to further investigate the lithium resource potential. Results were encouraging with respect to the level and consistency of the lithium contained by the clays. In 1980 and 1981, four core holes were drilled to obtain uncontaminated and undisturbed samples to more effectively determine lithium grades. After logging and analysis of the first two core holes, a portion of the core was sent to Chevron Research Company (CRC) to find an economic process for extracting lithium from the clays.
During the period of 1982 through 1987, Chevron drilled an additional 223 holes composed of both core and conventional rotary on lithium targets and conducted extensive metallurgical testing of the hectorite ores to determine amenability of the ores to extraction of lithium.
In 1985, Chevron produced polygonal resource estimates of the lithium at McDermitt (see table below). A cutoff grade of 0.25% Li, minimum thickness of 5 feet (1.52 m), and a minimum 9.0 ft% Grade Thickness (GT) were used for the estimate. The tonnage factor used was 17.8 ft3/short ton (1.8 g/cm3). The lithium resource is hosted in five pods of mineralization that Chevron designated the North, North Central, South, South Central, and PCD lenses that contain 2.276 million short tons of lithium or an equivalent of 12.1 million tons lithium carbonate. This estimate is not current and is not considered NI 43-101 compliant and is included here for historical purposes only.
Summary of 1985 Chevron Resources at McDermitt Caldera (M st = million short tons)
|Number of Holes||Area (Acres)||Deposit Thickness (ft)||Deposit Thickness (m)||Waste Thickness (ft)||Waste Thickness (m)||Average Grade (%Li)||Deposit Tons
|I - PCD||6||332||59||18.0||56||17.1||0.34||48||0.162|
|II - South||52||2,432||59||18.0||43||13.1||0.33||353||1.171|
|III - South Central||7||230||53||16.2||23||7.0||0.37||37||0.134|
|IV - North Central||10||372||66||20.1||41||12.5||0.34||60||0.207|
|V - North||21||1,364||59||18.0||64||19.5||0.31||196||0.602|
In 1991, due to the then relatively small size of the lithium market, Chevron sold their interest in the claims to Cyprus Gold Exploration Corporation. In 1992, it appears that Cyprus Gold Exploration Corporation allowed the claims to lapse and provided much of the exploration data to one of the claim owners from which they had leased claims.
Western Energy Development Corp., the U.S. subsidiary of Western Uranium Corporation, leased 33 claims in 2005 and the owner provided Western Energy access to the available Chevron data that included material on both the uranium and the lithium resources. Recognizing the potential significance of the lithium resource and the prospectivity the ground provided for hosting additional uranium resources, in 2005, Western Energy staked 1,634 federal lode claims covering the prospective areas. These claims cover much the same area as the original Chevron claims.
During the early part of 2007 Western Uranium recognized the potential for increased demand in lithium with the development of lithium battery powered hybrid/electric vehicles and made the decision to spin the asset out into an independently controlled company; Western Lithium Corporation. During the latter half of 2007 and into 2008 Western Lithium began a number of studies and activities that included the drilling of 45 core and reverse circulation holes on the PCD lens to verify and provide infill data on a pod of mineralization that is hosted in close proximity to a paved road and power. In early 2009 Western Lithium announced the southern-most Stage I (PCD) lens contained Indicated Resources of 48.1 million tonnes grading 0.27% lithium, or the lithium carbonate equivalent (LCE) of 688,000 tonnes LCE and Inferred Resources of 42.3 million tonnes grading 0.27% lithium, for an equivalent of 606,000 tonnes LCE, both at a cut-off grade of 0.20% Lithium. Additional drilling in 2008 on the upper more northerly lenses (WLC Stages II through V), which were originally identified by Chevron, confirmed the presence of lithium.
In addition to the drilling, preliminary marketing studies were initiated during 2007 along with bench scale metallurgical testing. To assist in evaluating the potential economic viability of the project a scoping study was completed in 2010 to assess capital and processing costs along with price sensitivity analyses. Additional drilling has been completed in 2010 and an interim updated resource has been published.