THE HIDDEN LAKE LITHIUM PROJECT
The Hidden Lake lithium project is located approximately 45 km east-northeast from Yellowknife (Figure 1) and can be reached by the all-weather Ingraham Trail Highway (Highway 4), and/or by charter helicopter or float plane. The Hidden Lake project hosts lithium-bearing pegmatite dykes that are part of the larger Yellowknife Pegmatite District (Figure 2). The pegmatites of the field have been described by Meintzer (1987) as the largest lithium resource in Canada with a minimum of 55,000,000 tons at 1.41% L2O primarily as spodumene. The project consists of 4 claims (Figure 3) with an aggregate area of 1,849 hectares.
High-grade lithium mineralization in light green to whitish spodumene was documented in outcrop with extensive channel sampling undertaken by previous workers. Channel samples defined significant lithium mineralization over substantial intervals for each of the four surveyed dykes, including a maximum value of 1.75% Li2O over 6.01 metres. Surface exposures of the pegmatite are laterally continuous for up to 800 m but are locally overlain by organic and inorganic soil (Figure 4). The strike length of the well exposed individual pegmatites is likely greater than the exposed 800 metres.
Figure 4. Surface exposures of a high-grade lithium dyke at the Hidden Lake lithium project.
Current Exploration Results
The Hidden Lake property was acquired in 2017 and the first ever drill program was successfully completed in 2018. A total of 1079 m of core was drilled to target pegmatite with high-grade lithium assays in surface outcrop.
Spodumene-bearing pegmatite was intersected in each hole varying from 2.65 m to 11.12 m in width. In drill core the spodumene occurs as <1 cm aggregates of anhedral ragged crystals to elongate subhedral laths that were up to 12 cm in length. Their colour varied from light green to whitish green and occurred in association with potash feldspar, albite, quartz, lesser muscovite and rare tourmaline. Variable hematitic and potassic alteration was observed in some pegmatite drill core intersections. Host rocks to the pegmatites are quartz-biotite-cordierite aluminous metasedimentary rocks.
Assay results confirm high-grade lithium mineralization has been intersected in four of twelve dykes on the property. The Li2O values vary from 1.0-2.0% over intervals up to 9.2 metres (Table 1). The high-grade nature of these spodumene-mineralized pegmatites coupled with the demonstrated favourable metallurgical characteristics demonstrated by previous operators makes these drill results significant. Assay results for each pegmatite dyke drilled in this phase of exploration are presented in Figure 5.
The next phases of exploration at Hidden Lake will include: (1) Mobile Metal Ions (“MMI”) soil sampling, as used to great success at the Company’s Zoro Lithium Project in Manitoba; (2) geological mapping; and (3) a second round of diamond drilling. The diamond drilling will assess the vertical and lateral extent of the high-grade lithium mineralization in the dykes drilled during Phase 1.