Lithium-cesium-tantalum pegmatite dyke swarms on the LNPG property have been traced over a combined length of 13 km in mountainous terrain that is deeply incised by several east- or west-facing cirques. The sampled portions of the dyke swarms are up to 52.60 m wide. Each dyke swarm contains multiple dykes that range from 0.2 to 10 m in width. The dykes strike northerly and have near vertical dips. They are well exposed on cirque walls, but most of these areas are too steep to sample. Fortunately, relatively continuous bedrock exposures are accessible at the base of cliffs on the north and south side of cirques. Cirque floors are covered by overburden.
During the 2016 field program, a total of 81 channel samples were cut across dyke swarms in two cirques (3 and 4) on the LNPG property (see attached map). The samples were cut using a hand-held rock saw. Channel samples are considered the most representative way to test surface exposures and are akin to diamond drill core in size and purpose. Channel samples were collected from the Prison Wall, Berlin Wall, Great Wall of China and Hadrian’s Wall dyke swarms within cirques 3 and 4. Highlights from individual dykes within and adjacent to dyke swarms include:
- 1.57 % Li2O, 250.3 g/t Ta2O5 and 0.95% SnO2 across 1.70 m;
- 2.04% Li2O, 57.8 g/t Ta2O5, 0.05% SnO2 across 4.00 m;
- 3.10% Li2O, 53.6 g/t Ta2O5, 0.03% SnO2 across 0.95 m;
- 2.33% Li2O, 59.0 g/t Ta2O5, 0.05% SnO2 across 1.20 m;
- 1.67% Li2O, 41.4 g/t Ta2O5, 0.03% SnO2 across 3.75 m;
- 1.83% Li2O, 67.3 g/t Ta2O5, 0.05% SnO2 across 1.25 m; and,
- 1.63% Li2O, 52.9 g/t Ta2O5, 0.01% SnO2 across 5.15 m.
The dykes are separated by sedimentary wallrocks including quartz sandstone, limestone and shale, which do not contain significant amounts of any elements of interest. Weighted average grade calculations for channel sampled intervals are reported in the following paragraphs and on Table I (attached). Wallrock separating individual dykes within dyke swarms was sampled in Cirque 4, and the values reported were uniformly low. When calculating weighted average grades for the dyke swarms, the wallrocks were assigned zero values for all elements. Weighted averages reported for dyke material within the dyke swarms omitted wallrock dilution.
A 16.80 m interval was channel sampled across an exposed portion of the Prison Wall on the north side of Cirque 4. The weighted average grade across this interval was 0.29% Li2O, 14.4 g/t Ta2O5 and 0.01% SnO2 over 16.80 m, including a total of 4.4 m of dyke material that graded 1.12% Li2O, 55.0 g/t Ta2O5 and 0.05% SnO2. Two individual dykes located 13 m and 27 m northeast of the dyke swarm were also sampled, and they returned 0.87% Li2O, 56.4 g/t Ta2O5 and 0.03% SnO2 across 1.90 m and 1.57% Li2O, 250.3 g/t Ta2O5 and 0.95% SnO2 across 1.70 m, respectively.
A 35.80 m interval was channel sampled across part of the Berlin Wall on the north side of Cirque 4. This interval yielded 0.29% Li2O, 12.3 g/t Ta2O5 and 0.01% SnO2 across 35.80 m, with dykes within it averaging 1.50% Li2O, 63.9 g/t Ta2O5 and 0.05% SnO2 across a total of 6.90 m. The best individual dyke within the dyke swarm returned 2.04% Li2O, 57.8 g/t Ta2O5 and 0.05% SnO2 over 4.00 m. On the south side of Cirque 3, a portions of the Berlin Wall swarm returned 1.00% Li2O, 21.3 g/t Ta2O5 and 0.01% SnO2 across 4.45 m, including 1.95 m of dyke material that graded 2.29% Li2O, 48.7 g/t Ta2O5 and 0.01% SnO2.
Great Wall of China
A 52.60 m interval across the Great Wall of China on the north side of Cirque 3 returned a weighted average grade of 0.38% Li2O, 20.7 g/t Ta2O5 and 0.01% SnO2. Within the 52.60 m interval, fourteen individual dykes were sampled for a total thickness of 16.65 m. The combined thickness of the dykes graded 1.21% Li2O, 65.4 g/t Ta2O5 and 0.03% SnO2.
A 19.70 m interval across a portion of the Great Wall of China on the south side of Cirque 3 averaged 0.50% Li2O, 21.3 g/t Ta2O5 and 0.01% SnO2 over 19.70 m, including four dykes totaling 7.00 m that graded 1.41% Li2O, 59.9 g/t Ta2O5 and 0.04% SnO2. An individual dyke located 77 m east of the Great Wall of China dyke swarm on the south side of Cirque 3 returned 1.63% Li2O, 52.9 g/t Ta2O5 and 0.01% SnO2 over 5.15 m.
A 10.35 m wide portion of Hadrian’s Wall was sampled on the south side of Cirque 3. This interval returned 1.13% Li2O, 71.1 g/t Ta2O5 and 0.03% SnO2 over 10.35 m. Within that interval, dyke material graded 1.86% Li2O, 116.7 g/t Ta2O5 and 0.05% SnO2 across 6.30 m. Twenty-five metres west of the 10.35 m exposure of the Hadrian’s Wall dyke swarm, two additional dykes returned 0.85% Li2O, 80.9 g/t Ta2O5 and 0.05% SnO2 over 1.05 m. The best dyke interval reported to date was 1.59% Li2O over 10 m (Wengzynowski, 2002). This dyke was not re-located in 2016. Two 2007 diamond drill holes returned high lithium oxide (Li2O) assays of 1.2% over 10.94 m (MAC 007) and 0.92% over 18.27 m (MAC 006). It is unclear if these intervals comprise single dykes or dykes and intervening wallrocks. The drill pad with collars for MAC 007 and 006 was relocated in 2016 on the ridge above the north side of Cirque 3. The drill core is stored at a gated compound at Finlayson Lake in southeastern Yukon.
Analytical work was done by ALS Minerals, with sample preparation and geochemical analyses in North Vancouver, British Columbia. All rock samples were analyzed for 38 elements by lithium metaborate fusion and inductively coupled plasma-mass spectroscopy (ME-MS81). All elements are reported as parts per million (ppm). The conversion factor from tantalum (Ta) to tantalum pentoxide (Ta2O5) is 1.2211, while the conversion factor from tin (Sn) to tin dioxide (SnO2) is 1.2696. Because the tin values were reported in ppm, the values had to be divided by 10,000 to give the tin value in percent. Ore grade lithium analysis was done by sodium peroxide fusion digestion and inductively coupled plasma -atomic emission spectrometry finish (ME-ICP82b). This technique reports in percent lithium and has a lower detection limit of 0.02% and an upper detection limit of 10%. The conversion factor from lithium (Li) to lithium oxide (Li2O) is 2.153.
The following steps would be beneficial for the advancement of the LNPG property:
1) Transportation of the 2007 diamond drill core from its current storage location near Finlayson
Lake to Whitehorse;
2) Re-logging of the diamond drill core to determine if dyke material was blended with
sedimentary wallrock material or if some dykes were not sampled. This would allow us to
confirm how the previously reported drill results compare to the channel sampling completed in
3) Data input and interpretation of the 3D survey information that was collected by the previous
4) Systematic prospecting and channel sampling throughout the property;
5) Investigation of pre-sorting technologies to separate mineralized dyke material from wallrock
6) Relationship building with the Nahanni Butte First Nation;
7) Permitting the land use application for advanced exploration activities on the LNPG property;
8) Diamond drilling near previous holes and the best channel sample locations.