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
A total of 9,979 m of drilling has been completed in 24 drill holes in five programs:
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 in the 24 holes completed to date at Hecla-Kilmer are provided in the
list of maps, figures and core photos on this Project Page
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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% Fe2O3.
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.
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 bedrock
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 with 17 % 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 013 respectively. Broad intersections with carbonatite dykes and vein breccia were obtained in two of the three new drill holes. In detail, and most significantly:
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there are six vein and vein breccia zones with > 1% TREO in hole 024 Pike Zone.
Mineralogy
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VR reported preliminary SEM results for REE mineralogy at Hecla-Kilmer on February 14, 2023, in NR23-004, and again on
October 17th in NR23-020 based on a more fulsome study by SGS on a bulk sample derived from the main, 361 m intersection of continuous REE mineralization in Hole 013.
The preliminary 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. Six samples were submitted, designed to span the 500 metres of vertical extent of REE mineralization in Hole 13 at Pike Zone, and mineralization in Hole 015 located 2.5 km to the south at South Rim Zone.
Crushed drill core assay rejects from the 461 metre intersection of continuous REE mineralization in Hole 013 were submitted to the SGS Lakefield laboratory in Ontario in May as a bulk sample for a mineralogical, beneficiation and metallurgical study. SGS is a recognized world leader in mineralogical and metallurgical studies on REE mineral systems. The intersection used for the bulk sample includes:
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361 m @ 0.96 % TREO(1) of which 20% are PMREO(2) and 2% P2O5 and including
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39 m @ 2.01 % TREO with 22% as PMREO.
The new chemical data on apatite are from TESCAN Integrated Mineral Analyzer (TIMA) analyses. Eight initial representative samples spanning the 361 metres of REE mineralization were crushed, sorted and analyzed with TIMA for elemental and mineral mapping of grains ahead of beneficiation studies. Key results include:
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The mineralogy shows that 80% of the REEs are contained within the phosphate mineral apatite, with the remainder hosted in monazite, a phosphate, and parisite-synchysite, fluorocarbonates, which themselves occur most commonly as fine grained inclusions in apatite.
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Apatite crystals contain around 80% of all REE mineralization at H-K, with an average concentration of
7.3% TREO;
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Over 75% of remaining REE mineralization occurs as small inclusions of monazite and parasite within apatite vein crystals and in apatite-fenite wallrock alteration;
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Permanent magnet REEs (PMREO) are up to 25% of TREO in the apatite, which is also enriched in neodymium compared to the finer grained REE-bearing minerals monazite and parisite;
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Carbonatites are a source of pure, clean magmatic phosphate used in electric vehicle batteries, and the apatite in the 461 m intersection in Hole 13 averages
37 wght% P2O5, starting at surface.
The results underscore the volume potential for REEs at Hecla-Kilmer based on the sheer breadth of phosphate intersections containing REEs, as shown
on the satellite image in the Maps section of this Project Page
. Importantly:
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The new REE mineralogy from the bulk sample does not change from bedrock surface to 461 m depth at Pike Zone:
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The new REE mineralogy at Pike Zone is consistent with mineralization at the South Rim Zone located 2.5 km to the south.
The new and detailed mineralogy is 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, starting in 2020, in order to better understand and document the character of the REE mineralization, including:
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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 the phosphate minerals monazite and apatite as the primary hosts for the 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 from 2020 through 2023, which demonstrated a nearly perfect, 1:1 correlation coefficient between P2O5 and TREO in more than 4,600 samples from all 24 drill holes.
SGS also reports that the 5-7 weight % REE contained in apatite at H-K is unique, even amongst other igneous deposits mined for phosphate in apatite. Further, the igneous apatite at H-K is pristine compared to the apatite in the world's sedimentary deposits mined for phosphate.
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 REE’s contained in silicate and/or refractory minerals; the REE mineralogy at Hecla-Kilmer related to phosphate and fluorcarbonate minerals is a clear distinction.
Summary of Key Attributes of REE mineralization at H-K
The discovery process at Hecla-Kilmer began with REE mineralization discovered at surface at Pike Zone in Hole 4 of the very first program in the fall of 2020. VR has intersected mineralized REE intervals with > 1% TREO in
18 of 24 drill holes completed to date, with a proportion of TREO as PMREO from 18-21 %, and up to 24%.
The lateral and vertical extent of the REE hydrothermal vein breccia and host fenite alteration system is significant. For example, at just the Pike Zone:
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243m @ 1.01% TREO in Hole 013, within 461 m of continuous mineralization @ 0.9% TREO;
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Continuous mineralization spans 461 vertical metres in Hole 013;
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Mineralization starts at bedrock surface at the base of till;
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Mineralization spans more than 1,000 m along the controlling north-south fault at Pike Zone;
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Mineralization in Holes 5 and 11 spans a width of more than 250 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 PMREO’s 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.
Phosphate is also abundant, and related directly to the REE mineralization process. The correlation coefficient is a nearly perfect at 1:1 between P205 and %PMREO in ICP-MS geochemical data from greater than
4,600 geochemical samples from all 24 drill holes completed to date. Carbonatites worldwide are a source of pure, clean magmatic phosphate used in electric vehicle batteries, and the apatite in the 461 m intersection in Hole 13 averages
37% P2O5, it starts at surface, it is coarse-grained, and it is
crystalographically pure. These results underscore the volume potential of the polymetallic system at Hecla-Kilmer based simply on the sheer breadth of phosphate intersections containing REE+Nb,
as shown on
the satellite image on this Project Page
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Geological Summary of REE Mineralization in Drill Core
VR has discovered critical metals mineralization within a large fluorapatite-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 known 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 to nepheline syenite, and including a myriad of more evolved dyke phases, including phoscorite and sovite carbonatite compositions, nepheline syenite porphyry and phonolite;
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Critical metal mineralization is most commonly associated with phoscorite dykes, ultramafic rocks comprising magnetite, apatite and either forsterite, diopside or phlogopite, and almost always associated with carbonatites. At H-K they are fluorapatite -rich hydrothermal breccia that varies depending on alteration facies noted below. The key minerals which host the REE’s include fluorapatite, monazite, bastnaesite, and parasite/synchisite, with the niobium contained in pyrochlore;
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A north-south fault controls hydrothermal fluids and separates calc-potassic and potassic alteration mineral assemblages. Calc-potassic alteration is dominated by amphibole and pyroxene with REE minerals found in medium grain calcite-apatite veins, and potassic alteration is dominated by coarse magnetite, biotite, apatite veins and intense biotite fenitization of wall rock. Both alteration facies come to surface, with the later potassic alteration being closely related to high-grade REE mineralization;
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Phonolite dykes are abundant and commonly have 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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Late stage alkaline magmatism, characterized by aphanitic ijolite to phonolite porphyry dykes are believed to be the overall driver of the intense hydrothermal alteration, brecciation and mineralization represented by sovite/phoscorite veins and dykes with variable fluorapatite, apatite and carbonate veins throughout all of the drill holes at H-K.