Houston Lake drills 66.05 m of 2.02% Li2O at Pak
2015-06-24 11:15 ET - News Release
Mr. Trevor Walker reports
HLM DRILLS IN-FILL ON THE PAK LITHIUM PROJECT INTERSECTING 2.01% LI2O OVER 66 METRES
Houston Lake Mining Inc. has released the results of four infill drill holes designed to increase the confidence level of the Pakeagama Lake pegmatite deposit model in preparation for an updated resource statement expected prior to year-end. The assay and collar data for the four holes reported are presented in the attached tables.
The intersection summaries, including the general location and purpose of the four drill holes, are outlined in the attached table. The table also summarizes the lithium, cesium, tantalum and rubidium grades for the four drill holes by mineralogical zones for the pegmatite intersections.
Highlights:
- Diamond drill hole DDH PL-020-15 intersected 2.02 per cent of lithium oxide over 66.05 metres from 79.5 metres to 145.55 metres;
- DDH PL-020-15 includes a 5.85-metre-wide lithium zone (upper intermediate zone or UIZ) averaging 4.15 per cent lithium oxide from 80.05 metres to 85.9 metres;
- Mineralization remains open to depth, and along strike to the northwest and southeast.
CORE LENGTH INTERCEPTS (PAKEAGAMA LAKE PEGMATITE) Targeting from the south-southwest 30 metres vertically below channel 18, and to test the DDH PL-020-15 depth extent of the granite/LIZ to the northeast of channels 18 and 19. Zone Width (m) Li2O (%) Ta2O5 (ppm) SnO2 (ppm) Nb2O5 (ppm) Rb2O (%) Cs2O (%) Rubidium plus tantalum-, cesium- and lithium-enriched zones 11.60 to 44.20 m 32.60 1.35 75 118 30 0.58 0.08 Including 11.60 to 36.00 m 24.40 0.60 70 114 25 0.69 0.08 Including 36.00 to 44.20 m 8.20 3.59 91 132 43 0.24 0.07 Lithium plus tantalum- and rubidium-enriched zones 79.50 to 145.55 m 66.05 2.02 103 121 61 0.30 0.05 Including 80.05 to 85.90 m 5.85 4.15 48 65 21 0.10 0.05 DDH PL-021-15 Designed to test from the north-northeast, the continuity of the LIZ above hole PL-011-14 and the UIZ below. Zone Width (m) Li2O (%) Ta2O5 (ppm) SnO2 (ppm) Nb2O5 (ppm) Rb2O (%) Cs2O (%) Lithium plus tantalum- and rubidium-enriched zones 53.60 to 68.75 m 15.15 1.20 107 101 61 0.32 0.02 86.20 to 121.20 m 35.00 1.24 94 100 78 0.26 0.02 128.90 to 149.00 m 20.10 0.97 129 92 79 0.15 0.04 Including 131.00 to 146.00 m 15.00 1.20 150 81 97 0.13 0.02 DDH PL-018-15 Designed to test from the north-northeast, the continuity of the LIZ above hole PL-13-003 and the UIZ 50 metres below. (Scissored PL-012-14; DDH-03 is 25 to 30 metres away to the ESE) Zone Width (m) Li2O (%) Ta2O5 (ppm) SnO2 (ppm) Nb2O5 (ppm) Rb2O (%) Cs2O (%) Lithium plus tantalum- and rubidium-enriched zones 46.60 to 60.20 m 13.60 1.60 107 70 65 0.29 0.01 77.60 to 93.40 m 15.80 0.54 162 85 88 0.26 0.02 100.55 to 122.00 m 21.45 0.75 80 115 57 0.21 0.02 Rubidium plus tantalum- and tin-enriched zone 137.65 to 143.85 m 6.20 0.34 136 339 89 0.27 0.06 160.75 to 168.15 m 7.40 0.22 144 196 98 0.11 0.03 DDH PL-015-15 From the north-northeast targeting 60 metres vertically below channels 18 and 19, and to test the depth extent of the granite/LIZ to the northeast of channels 18 and 19. The hole is above DDH-020-15. Zone Width (m) Li2O (%) Ta2O5 (ppm) SnO2 (ppm) Nb2O5 (ppm) Rb2O (%) Cs2O (%) Lithium-enriched zone 47.4 to 50.0 m 2.60 3.86 86 35 27 0.05 0.01 Lithium plus tantalum- and rubidium-enriched zone 68.75 to 73.05 m 4.30 1.28 185 58 59 0.22 0.04 Rubidium and tantalum-enriched zone 82.60 to 110.30 m 27.70 0.59 168 316 93 0.49 0.06 122.90 to 129.70 m 6.80 0.37 197 108 40 0.23 0.05 Notes: (1) The intervals in the above table are drill intersection widths. There are currently insufficient data to determine the true thickness of the pegmatite. (2) Lithium oxide content in the CIZ is predominantly associated with lithian micas and to a lesser extent (if any) in spodumene. Lithium oxide content in the lithium-enriched zones is predominantly associated with spodumene.
The upper intermediate (UIZ), central intermediate (CIZ) and lower intermediate zones (LIZ), and the wall zone (WZ), were previously described in the July 2, 2013, press release. Zones of sodic aplite are present in all holes and vary in width from tens of centimetres to several metres, and contain significant concentrations of tantalum, rubidium and cesium.
Noteworthy observations are that the north-northeast (footwall) boundary with the meta-sediments is consistent and predictable, while the south-southwest (hanging wall) contact with the granite is somewhat erratic, and complicated by granitic blocks and rafts, and appears to have been variably affected (meta-somatized) by the pegmatite intrusion event(s). The mineralized pegmatite remains open along strike to the west-northwest and east-southeast, and at depth. Granitic blocks/rafts mapped on surface appear to diminish with depth. The scissor pair of DDH-15 and DDH-20 show that the granite observed at surface and cut in the top of DDH-15 does not persist at depth where the deeper portion of DDH-20 cut pegmatite.
"We are pleased with these infill results from the phase III diamond drill program, as all of the holes consolidate the inferred and indicated resource estimate announced on Jan. 28, 2015," commented Trevor R. Walker, president of Houston Lake Mining. "The mineralized pegmatite intersections totalling 98.65 metres in DDH PL-020-15 will positively expand the current mineral resource estimate's tonnage."
Due diligence
All scientific and technical information in this release have been reviewed and approved by Peter J. Vanstone, PGeo, the qualified person under the definitions established by National Instrument 43-101. Under Houston Lake Mining's quality assurance/quality control procedures, the diamond drill contract specified NQ-sized drill core providing a 47.6-millimetre diameter sample. The drill holes were oriented perpendicular to the strike of the pegmatite and drilled continuously across it. Sample security and chain of custody started with the removal of core from the core tube and boxing of drill core at the drill site. The boxed core remained under the custody of the drill contractor, until it was transported from the drill to the secure on-site core shack facility by either the drill contractor or one of the company's designated personnel. At the on-site core shack, core boxes were opened and inspected to ensure correct boxing and labelling of the core by the drill contractor, photographed, and then reclosed. The core was stored securely until it was moved into the core shack for processing. The company geologists logged the core, and then marked and tagged it for sampling and splitting. Each core sample was assigned a tag with a unique identifying number. Sample lengths are typically one metre, but can be less depending on zone mineralogy and boundaries. The core was then reclosed and shipped to the company's off-site core splitting facility in Sudbury, Ont. Core marked for splitting was cut using a diamond core saw with a mounted jig to assure the core was cut lengthwise into equal halves. Half of the core was sent to an analytical laboratory for quantitative analysis of select elements. The remaining half of the core is retained and incorporated into Houston Lake Mining's secure, off-site core library.
All samples were assayed by Activation Laboratories Ltd., an ISO-accredited laboratory in Ancaster, Ont. Sample blanks, along with tantalum, lithium, rubidium and cesium certified reference material, were routinely inserted into the sample stream in accordance with industry recommended practices. Field duplicate samples were also taken in accordance with industry recommended practices.
About the Pak lithium project
The Pak lithium project lies close to the boundary between two geological subprovinces of the western Superior geologic province in Northwestern Ontario, and hosts a rare metals pegmatite deposit. The deposit is an LCT (lithium-cesium-tantalum) type pegmatite. These types of pegmatites have been the principal source of hard rock lithium, tantalum, rubidium and cesium ores mined in the world, but there are comparatively few commercially viable deposits.
Houston Lake Mining is actively exploring its 100-per-cent-owned-and-optioned project, which contains the Pakeagama Lake pegmatite. The deposit is one of the highest-grade lithium deposits in North America, which has a current indicated resource of 2.45 million tonnes of 1.81 per cent lithium oxide equivalent and an inferred resource of 5.91 million tonnes of 2.01 per cent lithium oxide equivalent, which has a technical/ceramic-grade spodumene with low inherent iron (below 0.1 per cent iron (III) oxide). The deposit has adjacent zones that are enriched in rubidium and tantalum. Houston Lake Mining is also evaluating the phased co-production of rubidium and tantalum concentrates once lithium mineral production has been commercialized.
The deposit has a known 400-metre strike length with an estimated true width varying from 10 metres to 125 metres with a subvertical orientation. The resource remains open to depth, and along strike to the northwest and southeast. The phase III, 1,500-metre diamond drill program was conducted with the objective to upgrade the lithium indicated mineral resource to a measured category, and to possibly upgrade the inferred mineral resource to a measured and indicated category.