Click to open National Instrument 43-101 compliant technical reports published regarding the Tatogga property:
Saddle North NI 43-101 Technical Report (August 2020)
Tatogga Property NI 43-101 Technical Report (August 2016)
The technical information on this website pertaining to geology, geochemistry, geophysics, soil and rock sample assays, and drill assays, has been reviewed and approved by GT Gold’s Vice President, Exploration, Charles J. Greig, P.Geo., a Qualified Person as such term is defined by National Instrument 43-101 Standards of Disclosure for Mineral Projects.
GT Gold has implemented the following quality assurance/quality control (QA/QC) procedures for the Saddle diamond drilling program:
NQ (47.6mm) diameter drill core is logged by geologists then sawn in half on-site, with one side bagged and labelled; the remaining half is placed in core boxes to serve as a permanent record and stored in core racks on site. Core sample lengths vary from 0.3 to 1.5 metres, though generally averaging a metre.
Control Sample Insertion
Control samples consisting of blanks and standards (one low-grade, one mid-grade, one high-grade), and field duplicates (1/4 split cores), are inserted sequentially at least every 20th sample into the drill core samples before shipment with control samples rotating sequentially through blank, low-grade, mid-grade and high-grade standards. Standards, each weighing 180 grams, consist of a low-grade (OREAS 501C (0.221g/t Au, 0.461g/t Ag & 0.276% Cu)), a mid-grade (OREAS 60D (2.47g/t Au, 4.57g/t Ag & 73ppm Cu)), and a high-grade (OREAS 62E (9.13g/t Au & 9.86g/t Ag)) gold+silver±copper standard sourced from Analytical Solutions Ltd. of Mulmur, Ontario. Blanks weigh +/- 2 kg each and consist of granite sourced from Terrace, B.C.
Every sample in the sample book ending in “XXXX44” or “XXXX89” is duplicated. Samples ending in 44/89 are the originals, and the next sample in sequence (4090) is the duplicate. The logging geologist staples tags for both original and duplicate together in the core box at the start of the original sample, and labels the duplicate sample tag with “DUP” in red permanent marker. The core cutter then cuts the sample normally, replacing the left half of core in the box, then cutting the right half of the core in half again. The left-hand quarter core is the “original” and the right-hand quarter core the “duplicate.”
Sample Preparation and Shipping
Individually tagged and labelled samples are placed in rice bags and each rice bag sealed with a numbered security tag. Samples are stored in camp or in a locked shed at Bear Paw Ranch Resort. Samples from a single hole are sent as individual shipments, with each shipment identified with a unique ID number. Security tag numbers are recorded prior to shipping and security tags checked upon receipt at the lab, then sent back to GT where they are checked against the recorded tag numbers. Samples are driven by GT Gold personnel from Bear Paw to the ALS Canada Ltd. (Minerals Division) sample preparation facility in Terrace, for crushing, pulverization and pulp preparation.
Upon arrival in Terrace samples are processed through the ALS sample tracking system which is an integral part of the company’s Laboratory Information Management System (LIMS). This system utilizes bar coding and scanning technology to provide complete chain-of-custody records for every stage in the sample preparation and analytical process, thereby helping to limit the potential for sample switches and transcription errors. Samples are then prepared as per ALS protocol PREP 31B using a jaw crusher, which is cleaned with compressed air between samples, resulting in 70% of the sample passing through a 10-mesh screen. A 1000-gram split of the crushed sample is then pulverized to 85% passing through a 200-mesh screen. In areas of specified higher-grade mineralization additional cleaning of crushers & pulverizers by ALS methods WSH-21 & WSH-22 is performed.
Pulps are then sent by ALS to their facility in North Vancouver, British Columbia, for multi-element analysis using Inductively Coupled Plasma (“ICP”) atomic emission spectroscopy, and standard fire assays for gold. The ALS facilities in Terrace and Vancouver are accredited by the Standards Council of Canada to the ISO/IEC 17025 standard.
Multi-element analysis is performed as per ALS protocol ME-MS61m, which involves the four-acid digestion of 0.25 grams of sample material, the residue of which is topped up with dilute hydrochloric acid and the solution analyzed by ICP-MS or AES for 48 trace elements, several of which (As, Pb, Cu, Zn) are important gold pathfinders in the Saddle mineralization.
For gold, fire assays are performed in North Vancouver as per ALS protocol Au-AA26 (0.01-100.00 g/t Au) using 50 grams of sample measured by (AA) atomic absorption. Over limit Au (>100 g/t Au) is additionally subjected to gravimetric reanalysis as per ALS protocol Au-GRA22. Selected samples are additionally sent for screen metallics analysis using the remainder of the pulp (~950 grams of sample). This step is taken to ensure that the coarse grained, nuggety gold fraction is captured.
Duplicate pulps and coarse rejects from the prepared samples are stored onsite by ALS for future reference.
Sample Batch Acceptance
QA/QC sample results are plotted by the managing Project Geologist using the QA/QC module of Geospark, an Access-based program from Geospark Consulting Ltd. Blanks fail if they contain >0.05ppm Au. Standards fail if they are more than 2 standard deviations above or below the accepted value for the standard. If two standards in a row fail or if a standard fails by >3SD, the entire analytical batch is rerun. If only 1 standard fails by <3SD, that standard is rerun with a shoulder of 5 samples before and after it (11 resamples). If all control samples pass, the batch is accepted. No sample batches are failed based on duplicates. In cases of strong disagreement between originals and duplicates, the lab reruns the original and the duplicate. If results of the second analysis are still very different, samples are collected from the retained core. If results are still different, those samples are flagged for coarse metallic reanalysis.
The Tatogga property is located in the very rugged Stikine region of northwestern British Columbia, Canada, on the Klastline Plateau, within the area generally referred to as the “Golden Triangle”.
Access is gained from paved Highway 37, which runs up the east side of the property. The nearest community is the village of Iskut and, some 70 kms to the north, the larger town of Dease Lake. Scheduled air services are available at Dease Lake, and helicopter and lodge services from bases in both communities, or nearby. The recently constructed BC Hydro Northwest Transmission Line, which serves the new Red Chris copper-gold mine to the east of Tatogga, provides high voltage grid power to the area.
The Tatogga property comprises a total of 47,500.29 hectares. Of this total, the Company either directly or through wholly-owned subsidiary New Chris, holds:
The topography on the Tatogga claims is diverse (photos, below), encompassing relatively flat to rolling hills atop local plateau areas, some precipitous mountain peaks and extreme slopes, and deeply incised valleys. Elevations range from about 823 metres (2,700 feet) above sea level in the valley bottoms to 2,103 metres (6,700 feet) in the upland areas. Vegetation consists primarily of poplar, alder, spruce and fir at the lower elevations but the plateaus are almost completely above the tree-line, which generally lies around 1,370 metres (4,500 feet). Permanent, though receding, glacial ice can be found locally on some of the steepest north-facing mountain slopes and nearby valleys, notably immediately adjacent to and south of the Saddle target area. Typical daytime temperatures range from the mid to upper 20s Celsius in summer to its precise opposite below zero in winter. Precipitation averages about 100 cm a year, with deep accumulations of snow common in winter.
Fieldwork (sampling, mapping etc.) can normally start at lower elevations in early June and at the upper elevations by July, continuing through to early October, weather permitting. The drilling season can in theory be considerably longer, potentially commencing in May and running through to November, subject mainly to wind and cloud conditions at upper levels, which can prevent flying to service operations. Drilling programs have continued well into November at the nearby Red Chris mine where weather conditions are similar.
The Company has to date and intends to operate in a manner that is respectful of the land, waterways and wildlife, respectful of the Tahltan First Nation upon whose traditional territories the Tatogga property is located, and respectful of the routines and traditional usages of the land by individual members of the Tahltan First Nation. The Company is and shall remain open in its communications, and will strive to ensure the community derives real and sustained benefit from its activities in the area.
GT Gold Corp. is in possession of a valid exploration permit from the B.C. Ministry of Energy and Mines, which allows for pending camp, drilling and related exploration activities on the Tatogga property. From time to time however, contingent upon exploration success, it may be necessary to apply under these permits for an expansion of the range or scale of activities envisaged.
The area now encompassed by the Tatogga property has seen sporadic exploration (mapping, geophysics, rock and soil geochemical sampling) in the years since 1959 by various operators such as Noranda Exploration, Teck Corp., and Ascot Resources. This work, detailed in the August 12, 2016, Tatogga NI 43-101 technical report, resulted in the discovery of a considerable number of base and precious metals showings, mostly concentrated in the southwestern portion of the property. However, of the two key target areas that currently constitute GT Gold’s primary exploration prospects on the property, only one - Pass Gossan - was historically known to prior operators. The more important target of the two - Saddle - is an entirely new find identified only in the period since 2013. The nearest and only historically known samples to the site of the Saddle discovery were five rock samples with elevated values of gold taken in 1991 by Brooklyn Resources from a site in the valley bottom about 1.5 km up-valley from the Saddle North geochemical anomaly, and never followed up.
GT Gold’s wholly-owned subsidiary, New Chris Minerals Ltd., acquired the Tatogga property in June 2011. Later that year and in 2012, most of the property was flown with magnetics. This work was followed in 2012 by initial mapping and, in 2013 and 2014, systematic geochemical soil (more than 1,800 samples) and rock sampling of the area that ultimately emerged as the Saddle target, as well as the Pass Gossan and adjacent Quash target area seven kilometres to the southwest. Clinton Smyth, P.Geo, shown below left, New Chris VP Exploration at the time, oversaw the planning and execution of these sampling and mapping programs, much of which was carried out in the field by or under the direct oversight of geologist Emily Miller (below, right). A ground based induced polarization (IP) survey was also carried out in 2014 over the Quash-Pass Gossan target area.
The Saddle Target is an entirely new gold prospect, comprised of two separate and sub-parallel WNW trending geochemical anomalies with associated induced polarization and magnetic anomalies that as presently understood cover at least 1.5 kilometres (Saddle South) and 2.4 kilometres (Saddle North) (map below).
Several factors may have resulted in the Saddle discovery being missed by early prospectors and geologists in the region. Until New Chris’s initial soil and rock sampling in 2013 and 2014, and initial drilling in summer 2017 by GT Gold, the immediate area of the target had had no known historical rock or soil sampling, or drilling. Exposure over the target area is poor, with extensive soil and alpine grassland covering the ridges (photo, below), and thick gravel deposits in the valley bottoms. Erosion may not yet have eaten down deeply into the mineralized system, resulting in little colour evident on surface, and little material to be observed in the drainages. The mineralization also appears to have very little of the quartz that would typically resist the effects of wind and water, standing up and attracting the eye post erosion.
The Origins of Discovery
Successive programs of rock and soil geochemical sampling by then privately held New Chris Minerals Ltd. (now a wholly-owned subsidiary of GT Gold Corp.) in 2013 (879 samples) and 2014 (939 samples), planned and overseen by Clinton Smyth, P.Geo (photo, below, left), with field execution by GIS Emily Miller (below, right), had demonstrated highly anomalous (i.e. >0.1 g/t) gold-in-soil across a broad area at Saddle. The company, then private, was unable to advance the property due to depressed markets, and it sat until early 2016.
In April 2016, well known B.C. geologist Charles Greig, P.Geo (photo, below left), reviewed the previous rounds of work and recognized the results as truly outstanding. Accordingly, in August 2016, he collected at his own expense a total of 33 sequential soil samples at ten metre intervals in a single line across the Saddle South anomaly. The 11 samples initially assayed returned an average value in soils of 0.80 ounces per short ton Au or 27.30 grams per metric tonne Au, with a median soil assay of 14.75 g/t Au. Given that a soil sample grade of 100 ppb (0.1 g/t) Au is typically viewed as noteworthy, and the low from the initial samples was 1500 ppb (1.5 g/t) Au, the 11 initial soil assay results were considered exceptionally strong.
In follow-up, a team of CJ Greig samplers was rushed back to the property where they collected, in early October working in the season’s first snow, a further 265 soil samples on a 25X25 metre grid covering the immediate area of the 33 August samples.
As shown on the maps below, the Saddle South anomaly contains an irregular core of very high gold-in-soil values as defined by contoured values exceeding 500 ppb (0.5 g/t) Au. This core of very high gold-in-soil values is itself encompassed by a considerably larger anomaly of lower tenor but still excellent values, as evidenced by the +100 ppb (0.1 g/t) Au contour on the maps below.
The Saddle South anomaly presently spans at least 1.5 kms in an east-west direction and, as shown on the maps below, contains an irregular core of very high gold-in-soil values as defined by contoured values exceeding 500 ppb (0.5 g/t) Au. Excluding a lobe of high gold-in-soil values in the eastern reaches of the anomaly, the core zone spans a distance of approximately 300 metres E-W by 225 metres N-S, and it remains open to the west under cover. This core of very high gold-in-soil values is itself encompassed by a considerably larger anomaly of lower tenor but still excellent values, as evidenced by the +100 ppb (0.1 g/t) Au contour on the accompanying figures. The +100 ppb Au anomaly remains open to both east and west within the 1.5 km-long Saddle South trend.
Discovery Drilling, July 2017
Following on the impressive results of the earlier rounds of soil geochemical sampling, the Company commenced in June this year, under the guidance and direct supervision of Charlie Greig, P.Geo, a first-ever drill program focused on the Saddle South portion of the broader Saddle target area. In the first stage of this program, a track-mounted RC drill was used to quickly prospect, in the absence of outcrop, various parts of the strong Saddle South gold-in-soil anomaly. Chips from the RC drill were then analyzed directly in the field with a portable XRF instrument for key pathfinder elements – As, Pb, Cu, Ag and Zn – known from the 2016 and previous years soil and rock geochemical work to accompany gold at Saddle (the portable XRF does not generally detect gold itself).
The expectation was that the early RC visual drill results (i.e. the presence of sulphide minerals), coupled with analytical results from the XRF, would vector the later RC drilling to the source of the gold-in-soil anomaly. This approach ultimately proved successful.
Following several early prospecting holes which did not return significant XRF values, the Company achieved a discovery intercept in hole TTR008, and by the latter half of the program was hitting in almost every hole, with several bottoming in mineralization. RC hole lengths ended up being considerably longer on average, and the number of holes ultimately drilled fewer than anticipated, due largely to the breadth of mineralization encountered.
By early July, with confidence established that the bedrock source of the strong gold-in-soil anomaly had been identified, the RC drilling program was wrapped up at a total of 28 holes for 1,527 metres. As announced July 25, 2017, assay highlights of the RC drill program were as listed below.
It should be noted that the widths reported below are drilled core lengths. True widths are estimated to be approximately 85-90% of drilled lengths for minus 50 degree holes, and approximately 70% for minus 70 degree holes. All assays are performed by ALS Canada Ltd. (Minerals), with sample preparation carried out at the ALS facility in Terrace, BC, and assays at the North Vancouver laboratory. Assay values are uncut. Assay results presented below are fire assay results only. For gold, fire assays are performed as per ALS protocol Au-AA26 (0.01-100.00 g/t Au) using 50 grams of sample with assays equal to or greater than 5 g/t Au calculated gravimetrically, and lower-grade samples measured by (AA) atomic absorption. All samples that returned equal to or greater than 5 g/t Au from initial fire assaying have additionally been sent for screen metallics analysis using the remainder of the pulp (~950 grams of sample). Selected samples running low gold but high values of As, Pb, and Zn have also been sent for screen metallics analysis. This step has been taken to ensure that any coarse grained, nuggety gold fraction that may have been missed in the fire assays has been captured.
RC Program Highlights: (see July 25, 2017 press release for significant intercepts from all 28 RC program holes)
Diamond Drill Program
A first phase of HQ-diametre diamond core drilling, planned initially to encompass just 2,600 metres, commenced with a single drill on July 6, 2017 in follow up to the RC drilling and a 16 line-km Induced Polarization (“IP”) ground geophysical survey completed in early July. The IP program had demonstrated the Saddle South mineralization to be coincident with an excellent IP response. The IP response, coupled with RC drill results, greatly improved targeting confidence for the core drilling down-dip and along strike of the defined zones at the Saddle South target.
Geology of the Saddle Discovery
Commenting on the Saddle prospect geology, Charles Greig, Vice President, Exploration, states: "The mineralization at Saddle South varies somewhat in style, but is essentially of intermediate sulphidation epithermal type. The highest-grade sections are characterized by semi-massive to massive quartz-carbonate sulphide veins and vein-breccias dominated by pyrite with subordinate sphalerite, galena, chalcopyrite and local sulphosalts. Closely associated are narrower quartz-carbonate-pyrite and pyrite veins and veinlets; the former are commonly well-banded, multi-stage veins with well-developed coliform textures. Also, closely associated with all sulphide-rich vein styles present at Saddle, are disseminations and somewhat coarser-grained irregular aggregates of pyrite that typically occur in halos around the veins – this style of mineralization also appears to be gold-bearing and, where well-developed, it provides excellent wallrock “support” for vein intersections. Alteration associated with the veins and their pyritic halos includes carbonate, Fe-rich chlorite, sericite, and silica with peripheral chlorite-Fe carbonate alteration.
The mineralized zones appear to follow an overall east-west trend along a steeply dipping structure, or structures, and this zone also appears to be the locus for emplacement of a series of largely post-mineral felsic, intermediate and mafic dykes. Mineralization, dykes and the host structure cut and are at a high angle to the moderately to steeply east-northeast dipping host fragmental volcanic and volcaniclastic rocks, and local flows, which are typically characterized by the presence of fine-grained hornblende and feldspar phenocrysts in both matrix, fragments, and clasts.
Saddle North: Large Geophysical Target Identified, and First-Ever Drilling
It was therefore considered encouraging when IP lines run on 200-metre centres across the area in June revealed, as shown in the image below, a large target coincident with and trending to the east for over a kilometer from the Saddle North geochemical target, where it remained open off the IP grid. The area is mostly covered by glacial drift but is otherwise at or close to surface. In consequence, two reconnaissance holes, TTD011 and TTD012, were drilled into the target area in July, as shown in green on the image below. Hole TTD011, the easternmost of the two holes, had to be abandoned prior to reaching target due to an influx of water, not before achieving however, a narrow intercept of Saddle South style epithermal vein mineralization, which ultimately returned (news, September 18, 2017) 5.97 g/t Au over 0.80 metres. On the other hand, hole TTD012, drilled 440 metres to the northwest of TTD011 proximal to the strongest part of the gold-in-soil anomaly, successfully drilled through target, returning 10.93 g/t Au over 1.71 metres, near true width, from a Saddle South style epithermal vein intercept.
Intriguingly, hole TTD011 also returned broad (i.e. from approximately 165 metres to total depth at 219 metres) porphyry-style intercepts of sub-economic copper-gold mineralization up and down-hole from the narrow epithermal vein intercept, with values ranging up to 0.31% Cu and 0.35 g/t Au in individual samples. In light of these results, and knowing the IP chargeability response continued off-grid to the east of TTD011, the decision was taken to extend the IP grid eastwards for approximately another 1.5 kilometres. This work was executed in August, resulting in the identification of a large, high-intensity IP chargeability anomaly anchoring the Saddle North system toward its eastern limits, coincident with a high tenor magnetic response (map, below).
In follow-up, four additional core holes were drilled into the Saddle North target in early October, three into the so-called “Northwest Arm” of the geophysical anomaly tested by holes TTD011 and 012, and a single near vertical hole (TTD062) into the core of the newly identified, large-scale anomaly anchoring the system at its eastern end. Encouraging, veining and alteration suggestive of the hot part of a porphyry system was achieved in hole 62 and assays are pending.
The Quash-Pass target (photo, below) is located approximately 7 kilometres southwest of Saddle. It is a historically known, but never drilled, porphyry prospect characterised by copper, gold, zinc and lead in talus and soils associated with an east-west striking monzonitic intrusion in contact with both Hazelton and Stuhini Group volcanic strata. The intrusion is believed to be the same age as the nearby Red Chris and GJ copper-gold porphyry deposits.
In the summer of 2012 a reconnaissance survey of 637 soil samples was undertaken by GT Gold subsidiary New Chris Minerals Ltd. in the Quash-Pass target area and the Quash region immediately adjacent to the southwest. This was followed, in 2013, with an in-fill sampling program of 1,384 soil samples undertaken over the anomalous areas delimited in 2012. At Pass Gossan, the copper assay results revealed a 1,200 by 200 metre copper anomaly of moderate intensity (100 adjacent samples with >150 ppm Cu, including 8 samples >500 ppm Cu) (map, below) trending along the north-facing plateau edge, coincident with or perhaps somewhat downslope from, the postulated location of a possibly sill-like monzonitic intrusion. Slopes are steep and talus cover is extensive, making first-hand observation of the stratigraphic relationships and contacts difficult.
In 2014, a 3D ground IP survey was completed (image, below) over the defined Quash-Pass target as well as the flanking Quash base metal (Pb-Zn) prospect. Chargeability targets were identified in the area of the Quash prospect, as well as along the eastern edge of the grid beneath anomalous levels of gold, zinc and copper in soils. These IP anomalies present potentially attractive future drill targets. However, before any drilling occurs extension of the IP grid to the east will be required to more precisely locate the eastern IP anomaly.
The Company intends to carry out additional exploration work at the Quash-Pass target. However, at the current time no precise plans have been formulated for doing so.
The Valleyside gold target is situated 1.2 km along strike to the southeast of the Quash-Pass prospect. It was for the most part identified through geochemical soil sampling carried out by New Chris Minerals in 2012 and 2013. However, evidence of the target existed prior to this in a historical line of ridge samples which now comprise part of the anomaly. The first of the figures below shows the gold assay results for the 2012-2013 work, which defined a 600 metre long anomaly, open to the east and west. Three adjacent samples reported above 300 ppb Au over a 50 by by 100 metre sampling area, including a maximum level of 918 ppb Au on the westernmost line.
Little is presently known about the geology of the Valleyside target, and it has yet to be mapped in detail by GT Gold. Encouragingly, the anomaly is strongly supported by arsenic which reaches 2,640 ppm in the highest gold sample. Arsenic and zinc (map, above) also delimit an anomaly of similar size on the northern side of the valley, where scattered anomalous gold values (50 - 100 ppb) are present.
The Company intends to carry out additional work at Valleyside. However, at the present time no precise plans have been formulated for doing so.