Hecla-Kilmer is amenable for the effective use of modern exploration technologies for base and precious metal deposits. Near-by towns with road access facilitate cost-effective exploration. Subdued topography is optimal for airborne geophysical surveys such as EM and magnetics. Historic drilling demonstrates that overburden thickness is in the range of 40 – 70 m, average for the region and easily penetrated by modern drilling technology. Historic and recent drilling also demonstrates that the hydrothermal breccia system comes to surface, that is, to the base of overburden and till, making the use of geophysics effective for basement targets.
VR completed the compilation, synthesis and interpretation of all available federal and provincial government regional data, and archived provincial mineral exploration assessment data in the Hecla-Kilmer area, and integrated it with the Ranoke project database.
The Company completed the first-ever airborne EM survey ever over the H-K complex in June, 2020, using the state-of-the-art VTEM+ system of Geotech Ltd. Flown at 100 m line spacing over a 6 x 7 km survey block for a total of 450 line-km, the data provide a high resolution of detail. The Company also had an independent, 3-D inversion of both magnetic and EM data completed for improved modeling for a potential magnetite-fluorite hydrothermal breccia body within the multiphase carbonatite complex. The Company also utilized a pre-existing, high-resolution, fixed wing airborne magnetic survey completed in 1993 by High Sense Ltd. as part of a regional diamond exploration program to improve the magnetic modeling.
There are two prominent, high contrast and deeply rooted MVI anomalies (magnetic vectorization peaks) in the northern and central part of the Hecla-Kilmer complex. The northern MVI anomaly correlates with the largest and strongest basement conductor identified in the VTEM+ survey; the central MVI anomaly correlates with the strongest overall magnetic signature in the Analytic Signal product.
A detailed, ground-based gravity geophysical survey was completed in March, 2021. It covers an area of approximately 1.5 x 3.5 km, with 597 stations completed in total; 573 on an equant grid station spacing of 100 metres, and 24 done on a 50 m infill pattern covering the main anomaly after it had been outlined by completion of the main grid.
Overall, the survey was designed to: 1. cover the main RTP magnetic boundaries within the large and concentrically zoned multi-phase carbonatite complex at H-K, and; 2. cover the main MVI anomaly derived from the 3-D inversion completed by VR in 2020 using the 1993 airborne magnetic data. The goal is to identify high-density centers of mineralization based on the high density XRF profiles of mineralization obtained from the scanning of the 2020 drill holes HK20-002 and 004.
The survey produced a large and high contrast anomaly in the northwest part of the complex, as summarized in the news release dated May 5, 2021. Anomaly attributes include:
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400 x 800m in size;
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3.5 mGal contrast to surrounding rock of the H-K complex;
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55 stations with no gaps within high density anomaly;
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Sharp boundaries define a dilational Riedel structure.
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The gravity anomaly is co-spatial with, but offset from, the northern MVI magnetic anomaly.
An ultra – high resolution, state-of-the-art drone magnetic survey was flown in the fall of 2021, and expanded in March of 2022. The objective of the survey is to: 1. clearly define the external boundaries of the overall complex, and; 2. identify internal magnetic contacts and gradients that are discordant to the magnetic zonation related to the primary igneous emplacement history of the multiphase complex, and are therefore potential targets for secondary hydrothermal veins and breccia with critical metals.
The final survey now covers an area of approximately 3.4 x 4.5 km and comprises 121 survey lines at both 25 and 50 m line-spacing for a total of 410 line-km. The survey produces a very high resolution of data because of the tight line spacing, the low “tree-top” flight altitude of just 30 metres above ground, and a computerized flight control paired with a new, very high sensitivity potassium-vapour magnetometer.
Summary of drilling
Fall, 2020
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Target: Magnetic anomalies in 3-D MVI inversion model of regional data
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1,971 m completed in 4 drill holes ranging from 351 – 609 m each
Fall, 2021
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Target: 3.4 mGal gravity anomaly, co-spatial with MVI magnetic anomaly
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2,604 m completed in 5 drill holes ranging from 468 – 561 m each
Spring, 2022
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Target: new AS magnetic anomalies from high resolution drone survey
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2,751 m completed in 8 drill holes ranging from 249 – 378 m each
Fall, 2022
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Target: delineate extensions of mineralization around Holes 13 and 15, respectively
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1,437 m completed in 5 drill holes ranging from 147 – 396 m each
Spring, 2023
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Test structures around Holes 1, 2 and 13 at Pike Zone for extensions to known mineralization.
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1,035 m completed in 3 drill holes ranging from 309 – 381 m each
A summary map and summary table with data for the key intersections of critical metals from the first 21 holes from the first four drill programs at Hecla-Kilmer are provided in the list of maps, figures and core photos on this Project Page. The geochemical data were obtained from a sodium peroxide fusion analytical technique designed to optimize the analytical detection for all of the rare earth elements.
First drill program, November, 2020
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Four drill holes on the northern MVI magnetic inversion anomaly, for a total of 1,971m. As announced on December 17th, 2020, VR intersected a fluorite-carbonate hydrothermal breccia body and high temperature, potassic alteration system with sulfide which
comes to bedrock surface, and has more than 500 m of vertical extent in two drill holes, HK20-002 and 004. Data from discovery Hole 004 were announced in NR-21-20 on October 26, 2021:
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58 m @ 0.38% TREO, incl. 1.44 % TREO over 3.21 m, starting at 40m, the bedrock surface at the base of till.
Second drill program, November, 2021
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Five holes were completed for a total of 2,604 m, targeting the 3.4 mGal gravity anomaly located on the western flank of the MVI magnetic anomaly that was targeted in 2020. Zones in the hydrothermal breccia with critical metals have high density profiles in XRF drill core scans, and thus provide a direct link between the gravity anomaly and prospective mineralization. A 299 m intersection of rare earth elements and niobium (REE + Nb) in Hole 5 was reported on
Nov. 16th in NR-21-22:
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299.5 m @ 0.47 % TREO, starting near surface at 52 m depth, and including up to 1.70 % TREO over 3 m from 156 m, within 28 m of 0.80 % TREO from 152 m;
Third drill program, April of 2022
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A total of 2,751 m were completed in 8 drill holes ranging from 249 – 378 m each, to follow-up on the broad, polymetallic intersections of critical metals in 2020 and 2021 by using the analytic signal (“AS”) magnetic anomalies derived from the new, ultra – high resolution airborne drone survey as an indication of higher concentrations of hydrothermal magnetite. Assays were reported for Holes 10 and 11 in NR-22-07:
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80 metres at 0.67% TREO within 131 metres at 0.41% TREO in Hole HK22-010;
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13 metres at 0.94% TREO within 88 metres at 0.50% TREO in Hole HK22-011.
Individual one metre samples from the 13 metre intersection in Hole 11 contain up to 2.3% TREO, up to
39.1% Fe2O3, and up to 11.2% P2O5.
Assays were reported for Hole 13 in NR-22-08 on July 21st:
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243 metres @ 1.01 % TREO, of which 19% are PMREO,
within 290 metres @ 0.91 % TREO starting at surface
and continuous from top to bottom in Hole HK22-013,
and including:
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65 metres at 1.66 % TREO, starting at 155 metres, and including:
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39 metres @ 2.01 % TREO starting at 155 metres.
1. The 65 metre interval of 1.66% TREO is made up of 24% Magnet REO (Nd, Pr, Dy, Tb);
2. The 15 metre interval with 2.14 % TREO contains 15.71% P2O5 and 13% Fe203.
In addition to the afore-mentioned mineralization, VR discovered two new areas with Critical Metals located 1.5 and 2.5 km to the south of Pike Zone, respectively, in the central core and south rim of the complex, as announced in NR22-10 on August 18, 2022. For example, on the south rim of the complex:
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25.5 metres @ 1.131% TREO with 18% as Magnet
REO*, within 55.2 metres @ 0.70% TREO
starting less than 30 metres from bedrock surface in Hole HK22-015.
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* % Magnet REO: is PMREO
divided by TREO
(total rare earth oxide) and expressed as a percent.
PMREO is the sum of the high-value rare earth oxides
Pr2O3 +
Nd203 +
Tb2O3 +
Dy2O3 used in permanent magnets
for wind turbines and electric vehicles.
Fourth drill program, November, 2022
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Five drill holes were completed for 1,437m. The goal of the fourth program was to complete additional drill holes into the two main areas with known higher grade critical metal mineralization around Hole 13 at Pike Zone and Hole 15 at South Rim in order to begin the assessment of their potential for mineral volume.
Hole 13 in the third drill program was extended to 504 m at the start of the fourth drill program. It is worth repeating the Hole 13 intersection announced in NR22-18 on January 17, 2023.
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Drill Hole HK22-013: 361 m @ 0.96 % TREO (1), of which 20% are PMREO(2)
within 461 m @ 0.85 % TREO + 0.13% Nb2O5, starting at
surface, and including:
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39 m @ 2.01 % TREO within 66.6
m @ 1.57 % TREO with 20% as
PMREO.
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The hole ends at 504 m with 2 m @
2.84 % TREO and 1.1 g/t gold.
Gold increases with TREO grades, and is
associated with REE mineralization in monazite.
Salient features of the 461 m intersection of continuous REE mineralization in Hole 13 include:
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Mineralization starts at the bedrock surface, below an overburden of glacial till;
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Mineralization is continuous in nature, from bedrock surface to the end-of-hole at 504m;
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The REE mineralization remains open to depth, and is as strong as any REE interval higher in the 461 m intersection; there are no systematic changes down the hole in geology, density of carbonatite dykes and veins or intensity of potassic alteration;
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There are 49 one metre samples with > 2% TREO, and they span the entire 504m hole;
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The proportion of the high value PMREO does not vary from the range of 17-22% of TREO;
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Gold mineralization at the bottom of the hole correlates with a corresponding increase in REE mineralization, and is part of the same polymetallic fluid system.
High grade mineralization at the South Rim zone located some 2.5 km to the south of the Pike Zone was also confirmed and extended, as reported in NR23-002 on January 23, 2023.
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Drill Hole HK22-020: 212 m of continuous mineralization at 0.7% TREO with17 % PMREO, with one metre samples up to 2.7% TREO(1) with 28.5% PMREO(2), and including 48 m @ 1.0 % TREO with 19% PMREO at the end of the hole, and open to depth.
Fifth drill program, May, 2023
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Three drill holes were completed for 1,035 metres in three different areas of REE critical metal mineralization at Pike Zone, around Holes 001, 002 and Hole 13 respectively. Geochemical data are expected in the fall of 2023. The objective of the drilling is to assess the structural controls for REE mineralization, and by extension, the parameters for mineral volume at the Pike Zone.
Mineralogy
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VR reported positive results for REE mineralogy at Hecla-Kilmer on February 14, 2023, in NR23-004:
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Scanning electron microprobe (SEM) confirms PMREO minerals hosted in monazite and parisite, phosphate and fluorocarbonate minerals, respectively.
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The REE mineralogy is consistent. It does not change through the 461 m vertical intersection of continuous mineralization starting at surface at Pike Zone, and it is the same 2.5 km away at the South Rim Zone.
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Monazite has proven REE extraction, and it is the focus of new REE facilities in Canada.
The new mineralogy data are from an electron microprobe (EMPA) equipped with an Energy Dispersive Spectrometer (EDS). The work was completed by Renaud Geological Consulting Ltd. (RGC) based in London, Ontario, who have extensive experience on REE deposits in Canada. The six samples submitted for this study were designed to span the 500 metres of vertical extent of REE mineralization at Pike Zone, and mineralization 2.5 km away at the South Rim.
The new SEM results are entirely consistent with results obtained from all of the state-of-the-art technologies which VR has utilized from the very beginning of its exploration at H-K in order to better understand the REE mineralization. The new SEM data on monazite are not surprising:
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QEMSCAN analyses in 2020 by SGS Canada, Lakefield, which determined the styles of mineralization and alteration, and confirmed the role of monazite and apatite, a phosphate mineral, for hosting PMREO;
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Whole-core XRF scanning on site in 2021 by GeologicAI of Calgary, which improved real-time decision making for drilling, and confirmed the correlation between TREO and P2O5;
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Lithium-borate fusion to optimize REE detection in drill core geochemical samples;
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Electron microprobe analyses (EMPA-EDS) in 2023 by RGC in London and reported in this news release to confirm monazite and parisite as the host minerals for the individual Permanent Magnet REO’s, both in apatite veins and in carbonatite breccia cement: Figure 5, Figure 6.
The monazite mineralogy is important. Canada is plagued with REE discoveries made during the past 60 years that have never been developed because of the difficulty in extracting and recovering REEs contained in silicate and/or refractory minerals. REE beneficiation from the sulfate mineral monazite is proven however, so the two new REE processing facilities that have been recently built in Saskatoon and in Utah in order to bolster domestic raw material supply for the EV industry in North America are both designed around REE concentrates with monazite mineralogy. As such, it is a significant milestone for the Hecla-Kilmer project that the new EMPA-EDS data confirm that the Permanent Magnet REO minerals are hosted in monazite and parisite.
Next Steps
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VR has initiated a full metallurgy and beneficiation study using a bulk sample obtained from the entire 461 m intersection of continuous REE mineralization in drill hole HK22-013, starting at surface in the Pike Zone. Sample material was sent to SGS Lakefield in Ontario in June, 2023; results are expected by the early fall. SGS is a recognized world leader in REE metallurgy and extraction research, and this work on Hole 13 will benefit from their REE mineralogy studies of mineralized samples of drill core from H-K during the past two years.
Summary of Key Attributes of REE mineralization at H-K
The discovery process at Hecla-Kilmer began with REE mineralization discovered at surface in Hole 4 of the first program in the fall of 2020. VR has now intersected high grade critical metal mineralization with > 1% TREO with a proportion of PMREO from 18-21 % in
16 of 21 drill holes completed to date. Drilling is still at a very early stage at H-K, yet the 21 holes demonstrate the lateral and vertical breadth of the hydrothermal breccia and alteration system with critical metals at Hecla-Kilmer. For example, in just the
Pike Zone alone in the northwest part of the complex:
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Continuous mineralization of 1.01% TREO for 243m in Hole 13, starting at surface;
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Mineralization in Holes 002 and 004 spans more than 500 vertical metres;
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Mineralization in Hole 005 spans 299 m length;
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Mineralization in Holes 008 and 009 spans 1,000 m along the long axis of the controlling north-south fault.
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Mineralization in Holes 5 and 11 spans a width of more than 500 metres on either side of the controlling north-south fault
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There is mineral potential along more than 1,200 m of strike on the offsetting, east-west fault which focuses veins, dykes, breccia and mineralization in Holes 11, 14, and 17.
The importance of the high proportion of the four PMREOs in REE mineralization at Hecla-Kilmer is worth re-emphasizing. This ratio is important because of the high price of the PMREOs, such as neodymium and terbium, in response to the demand for permanent magnets in electric vehicles and wind turbines. That demand-based value is amplified by scarcity; that is, they are absent from most REE carbonatite deposits globally. For comparison, published resources for most Canadian LREE deposits in carbonatite typically contain between 12-15% PMREO of TREO, which is roughly 40% lower than the 19-22% proportion on average at H-K, and up to 24% in Hole 13.
The polymetallic nature of mineralization at H-K is also important. The intersection of 0.27% Nb over 80 metres in Hole 10 compliments the 237 metres @ 0.2% Nb in Hole 5 from last year, with TREO of 0.5 - 0.67 % on average across both of the broad intersections, and up to 2.3% locally. The value of the Niobec deposit in Quebec, the worlds’ largest, provides an analogue for the value-potential at Hecla-Kilmer for niobium alone, given the sheer volume of calc-potassic and potassic alteration facies along structures with Nb + REE mineralization.
Finally: grade comparison to global deposits. The 0.91 – 2.14 % range in TREO content in the various intervals in the 290 metre intersection in Hole 13 is comparable to the range of 0.4 – 1.73 % TREO reported for the average resource grades of eight of the top ten REE deposits globally. Just as important, the proportion of the four PMREO’s in the REE mineralization at Hecla-Kilmer matches, or exceeds
best of breed global REE mines at Bayan Obo in China and Mtn. Pass in California.
To summarize, the upside potential of the REE mineralization at H-K relates to:
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The breadth of the intersections made to date, the sheer scale of the host hydrothermal breccia system both laterally and vertically, and the discovery of three different areas of mineralization now, all starting at surface, and located across 2.5 km of the complex, from the northwest quadrant to the south rim;
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The polymetallic nature of the critical metal mineralization, including both the light and heavy rare earths, niobium, phosphorous and iron;
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The composition of the REE mineralization; it contains a high proportion of the four, high value rare earth elements used in permanent magnets and essential for the manufacturing of EV’s and wind energy turbines – this REE distribution drives an unusually high in-situ basket value of the mineralization at H-K;
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Depth and location: the mineralization comes to bedrock surface at the base of till, and the project is located less than 25 km from Ontario grid power and active rail and highway infrastructure.
Geological Summary of REE Mineralization in Drill Core
VR has discovered critical metals mineralization within a large fluorite-apatite-magnetite hydrothermal breccia and carbonatite vein and dyke system hosted within a ultra-high temperature, calc-potassic and potassic alteration system with sulfide which comes to surface, and has more than 500 m of vertical extent.
Drill core photographs with examples of the style of mineralization and alteration which hosts the REE’s are shown at the end of the list of maps and photographs which follow this text summary.
Key geological attributes in drill core to date include:
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High temperature alteration assemblages completely overprint and/or replace original, alkaline and ultrabasic rocks ranging from essexite and ijolite in the outer ring to very coarse nepheline syenite at the core. The coarse grained alkaline intrusive system is subsequently cut by a myriad of dyke phases with various fine grained and porphyritic textures of mafic ijolite and more evolved nepheline syenite, and hydrothermal veins and breccia infill of sovite (calcite rich) and phoscorite (apatite-REE rich) carbonatite compositions;
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Critical metal mineralization is most commonly associated with sulfide-bearing carbonatite dykes, fluorite-carbonate-apatite veins and magnetite-rich hydrothermal breccia. The key minerals which host the REE’s include monazite, bastnaesite, fluorapatite and apatite, with the niobium contained in pyrochlore;
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Several locally extensional faults control hydrothermal fluids and separates calc-potassic and potassic alteration mineral assemblages. Calc-potassic alteration is dominated by amphibole and pyroxene and includes pyrochlore and sulfide, and potassic alteration is dominated by magnetite, biotite, apatite and carbonate. Both alteration facies come to surface.
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Porphyritic ijolite dykes are abundant and appear to be correlated with phoscorite (apatite-REE rich carbonatite) veins and vein breccias. The intrusions are intensely altered and are commonly elevated in gold, with 15-184 ppb gold over several + 40 metre intervals in drill hole HK20-002 located on the north-south fault which controls hydrothermal fluids and separates different alteration facies.
More generally:
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Pyrite, pyrrhotite, marcasite and lesser chalcopyrite occur as seams and clots in fluorite-calcite veins and poly-lithic hydrothermal breccia, and as disseminated grains in carbonatite dykes. There are assays in 1m samples of up to 0.12% Cu (1240 ppm) in zones of intense fenitization (potassic alteration);
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Dark, commonly red-hued polylithic magmatic-hydrothermal breccia is throughout most of the drill holes. It overprints all rock types. The groundmass contains carbonate, fluorite, biotite, magnetite and chlorite. It both disaggregates and digests carbonatite dykes with sulfide, and is itself cut by carbonatite dykes and fluorite-carbonate veinlets with sulfide and pyrochlore;
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Alkaline, nepheline syenite porphyry dykes and sovite/phoscorite carbonatite dykes with variable fluorapatite, apatite and carbonate veins occur throughout all of the drill holes, and are believed to be the overall driver of the intense hydrothermal alteration, brecciation and mineralization at H-K.
Drilling is still in the very early stages at Hecla-Kilmer, yet it is already clear that the REE + critical metals component of the hydrothermal vein and breccia system has significant value potential, based on:
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The breadth of the intersections made to date, and the sheer vertical and lateral scale of the hydrothermal breccia and high temperature alteration system;
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Discovery of three different areas of mineralization in the northwestern quadrant, central core and south rim of the complex respectively, spanning a distance of some 2.5 km;
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The polymetallic signature of mineralization, including both the light and heavy rare earth elements, niobium, phosphorous and iron, and anomalous copper and gold locally;
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The REE mineralization contains a high proportion of the four, high value rare earth elements used in permanent magnets and essential for the manufacturing of EV’s and wind energy turbines – this REE distribution drives an unusually high in-situ basket value of the mineralization at H-K;
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TREO’s and Nb maintain average grades over broad intersections which are comparable to the average grades reported for REE deposits globally, and the proportion of the high value PMREO’s in the TREO mineralization a H-K matches or exceeds that in global
best of breed REE mines;
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Depth and location: mineralization comes to bedrock surface at the base of till, and the project is located less than 25 km from active rail, grid power and highway infrastructure.