The Reveille project is located along the northern margin of the of the Walker Lane belt in west-central Nevada. It occurs on the western margin of a Tertiary-aged rhyolite volcanic centre named the Goblin Knobs caldera. It is analogous in age and setting to the Big Ten caldera located some 75 km to the northwest, along trend, where the Company has been exploring low-sulfidation epithermal gold-silver veins and alteration systems since 2016.
Roads and trails throughout the Reveille property facilitate cost-effective exploration, in combination with easy access to the property on Highway 6 from the nearby town and regional service hub of Tonopah, Nevada.
The opportunity for VR at Reveille is threefold. First, the consolidation of the various showings on the current property by the property vendor allowed VR to explore the large array of showings and workings, that is, the district, both collectively and systematically for the first time in the 140 years of prospecting in the region, beginning in the 1870’s. Second, VR will use modern exploration technologies and apply new carbonate replacement deposit (“CRD”) and porphyry copper mineral deposit models developed for the North American Cordillera for the first time across the district in order to evaluate, prioritize and drill test the wide array of vein, manto and breccia-pipe occurrences. Third, and finally, although there are historic workings including local underground drifts and larger surface pits across the property, there is no previous diamond drilling on any of the showings exposed in the hills, nor any drilling on the western flank of the range to explore for buried deposits under the valley cover and in proximity to the regional range fault and caldera ring faults which form the western flank of the range itself.
VR reviewed the property for more than a year prior to the acquisition in June of 2020, including two site visits. Experience gained by exploration on our nearby Big Ten project located in a similar Tertiary volcanic caldera setting has been applied to our work at Reveille. The Company then completed a wide array of property-scale surveys at Reveille during the second half of 2020, including several different airborne geophysical surveys and numerous “boots on the ground” mapping and geochemical sampling programs.
First pass drilling of new targets on the western range flank was done in the spring of 2021, with four reverse circulation drill holes (“RC”) between 1,000 and 1,200 ft long each completed for a total of 4,347 feet, and one diamond drill hole was completed to a depth of 110 m on the new, G1 breccia pipe target. A 3D array DCIP ground geophysical survey covering the entire western flank of the range and western portion of the property was completed concurrent with drilling. A large, high amplitude IP anomaly was identified at the southwest end of the northeast-trending structural trend mapped on surface which controls the high grade silver-copper mineralization exposed in the hills of the Reveille range to the east. It is named Kawich. It is large at nearly 600 m in diameter, and near-surface, with a depth-to-top of approximately 120 m, at the base of the volcanic cover in the valley.
Phase II of the first-pass RC drilling at Reveille was completed in July, 2021. The main objective was to test the Kawich IP anomaly as the potential core of the overall mineral system at Reveille. Four holes were completed from between 350 and 450 m each, for a total of 1,552m.
The drill hole at G1 encountered continuous broken core through a diatreme-like breccia body for 110m, with up to 96 g/t silver over 0.61 m, and ending in breccia with 11.8 g/t silver over 0.61 m. Both drill holes at Kawich intersected continuous pyrite alteration over 450 ft thick in de-calcified, dolomitized limestone. Geochemical data from more than 2,000 RC and drill core samples define a robust, copper-silver-moly-tungsten-antimony signature.
G1 and Kawich are new discoveries; they expand the breadth of the Reveille system westward from the exposed range where the historic workings are located, and they confirm the presence of a strong hydrothermal gold component to the district-scale polymetallic mineral system. But perhaps most importantly, the high temperature, base metal signature for the broad, gold-bearing pyrite alteration facies at Kawich demonstrates its potential as a large-scale porphyry center and driver for the high grade but distal polymetallic showings scattered across the range at Reveille, which is what VR came to this historic district to explore for.
The Company will fully integrate and fully interpret an extremely large data set from the continuous geochemical sampling and hyperspectral scanning of all nine drill holes completed in 2021 in order to formulate a plan for follow-up drilling in 2022. We anticipate the focus to be on the large, gold-bearing pyrite alteration system at Kawich given its sheer size, and the clarity of the high-temperature geochemical and hyperspectral mineral vectors towards Kawich which are already evident from the first-pass analysis of the data.
The Reveille property is located in Nye County in west-central Nevada. It is approximately 90 km’s east of Tonopah, Nevada, with access via Highway 6 to Warm Springs, Nevada. Local roads and trails provide excellent access both around and within the property itself.
The property is located within the southern part of the Reveille range. Topographic relief on the property is just over 1,000 feet, with the central, ridgeline axis reaching 7,900 feet in elevation.
Outcrop is extensive, and the predominance of limestone limits vegetation to grasses and sage, with sparse and stunted juniper. Where there is cover, colluvium is interpreted to be thin and local in nature. Soil profiles are poorly developed; fine, light brown colluvium normally gives way to more rubbly-weathered outcrop material within a half metre of depth, or less.
The Reveille property consists of 128 mineral claims in one contiguous block covering 2,619 acres (1,059 hectares) over an area of approximately 2 x 5.5 km.
The property is on federal land administered by the BLM, and is outside of the BLM’s broadly defined area of sage grouse protection.
The property is owned 100% by VR, registered to the Company’s wholly-owned US subsidiary registered in Nevada. The general terms of a binding Acquisition Agreement dated June 22, 2020, are provided in a news release of the same date, with Closing announced on June 25, 2020.
There are no underlying annual lease payments on the property, nor are there any joint venture or carried interests on the property. There is a 3% net smelter returns royalty registered on the property, with an industry-standard buy-down provision granted to VR.
Summer - Fall 2020
Overall, the Company has synthesized and integrated regional and property-scale data for Reveille, in conjunction with an already established GIS workspace for our nearby Big Ten epithermal gold project hosted in the Big Ten Tertiary volcanic caldera which is of similar age and character to the Goblin Knobs caldera at Reveille. The goal is twofold:
- evaluate each of the numerous individual silver-copper showings and historic workings in the range on their own merit and stand-alone upside potential, and;
- evaluate the potential in the covered valley immediately to the west of the range for the for the large-scale source and driver to the overall CRD mineral system responsible for the high grade silver-copper showings located up in the hills of the Reveille range.
The access, climate and topography at Reveille afford effective and efficient year-round exploration. A comprehensive set of ground and airborne geophysical, geological and geochemical surveys were completed at Reveille during the second half of 2020, designed to cover the entire silver-copper mineral system at Reveille, and identify and prioritize targets for high grade silver mineralization. Importantly, this is the first modern and systematic exploration ever done over the collective group of showings at Reveille, and in the context of current CRD mineral deposit models.
The bulleted list below illustrates the extent of exploration done and the depth of data acquired in 2020 and 2021 from an array of surveys exploiting the most modern technologies available:
- Airborne Hyperspectral survey completed in June, 2020, with 2 m resolution across 320 spectral channels for high resolution mapping of alteration minerals over a 100 sq km area, centered on the property.
- High resolution VTEM+ airborne EM survey completed in July, 2020, with 100 m line spacing over a 3 x 4.5 km area:
- RTP and TMI magnetic maps for mapping; resistivity maps and conductivity products for identifying sulfide-bearing breccias, vein stockworks and massive sulfide mantos.
- High resolution ground gravity survey completed in July, 2020, with 638 stations in an equant, 100 m station grid covering a 2 x 3.5 km area, with and additional 101 additional infill stations completed in November, 2020:
- Map structures and identify potential high-density sulfide bodies below surface showings.
- Detailed geologic mapping and sampling of the entire property completed in July, 2020:
- Systematic rock sampling of high-grade silver veins, and silver-bearing mantos and breccia bodies in order to establish geochemical zonation across the entire mineral system, and to prioritize drill targets amongst the various high-grade silver showings at surface:
- 253 rock samples for geochemistry overall, property wide;
- 182 rock chip samples for spectral analysis for alteration mineralogy;
- 6 samples for petrography;
- 287 soil samples on 15 lines collected in November, 2020 through March 2021, over the entire western third of the property and covering the break-in-slope on the western flank of the range and extending upwards of 2 km’s westward over the pediment valley.
The detailed geological mapping completed by VR has determined the precise stratigraphic position of mineralization, and importantly the preferred structural controls to hydrothermal fluids, something that has not been identified or described by previous workers in the district.
Spring - Summer 2021
VR completed two major programs in the spring-summer of 2021:
3D-array DCIP ground geophysical survey
The IP survey covers the western flank of the range and the entire western third of the property. The grid area of approximately 1.5 x 2 km’s comprises 10 read lines with 131 receiver stations on an equant 150 m station grid which generated approximately 188,000 chargeability data points for the 3D inversion models.
Resistivity data are used to map alteration minerals and facies, and chargeability data are used to map potential sulfide mineral concentrations. The IP survey allows VR to explore below the valley cover west of the range where the historic and high grade silver-copper showings are exposed at surface. A strong (>30 mV/V), large (450 x 600 m core) IP anomaly is apparent in the covered valley, near-surface and immediately below the cover of volcanic rocks in which both sodic and potassic alteration is mapped on surface both above and peripheral to the anomaly. It is named Kawich, and importantly is “on trend” with the northeast-southwest structural corridor mapped at surface by VR which controls the high grade silver-copper mineralization in the historic workings in the hills.
First-pass RC drilling
Eight RC drill holes and one diamond drill hole were completed on and around the G1 and Kawich targets on the covered, western flank of the Reveille range in 2021 for a total of 2,987 metres. Continuous geochemical sampling was completed on each hole, for a total of 2,187 samples. The Company has data for gold by fire assay, and for 62 elements by ICP-MS.
Phase I drilling of four RC (reverse circulation) drill holes was completed for a total of 1,325 m (4,347 ft), with each hole between 1,000 and 1,200 ft long. Continuous geochemical sampling was done on every 5 ft run in each hole, and both LWIR and SWIR hyperspectral scanning was completed on each hole in its entirety in order to map alteration minerals. The specific targets for each drill hole in the Phase I program included magnetic, conductivity, resistivity and gravity anomalies on the western flank of the range where there are geochemical vectors towards the high temperature source of the overall silver and copper CRD hydrothermal system at Reveille which formed the array of surface showings in the range to the east.
A diamond drill core hole was completed to a depth of 110 m on the G1 gravity low and target for a de-calcified jasperoid hydrothermal breccia pipe. Breccia was intersected from top to bottom in the hole, with quartz veinlets and mm-scale sulfide casts (pyrite) hosted in bleached, decalcified limestone. Broken core rubble was experienced from top to bottom because of the fracturing, hydrothermal shattering, quartz veining and decalcification and breakdown of host limestone during formation of the breccia body.
Phase II drilling of four RC holes was completed in July, 2021, for a total of 1,552 m. Phase II followed up on the geochemistry results from the four Phase I drill holes completed in March, and it tested the Kawich anomaly that was delineated in the expanded 3D array, DCIP geophysical survey completed in May.
The key initial finding from the first pass RC drill program at Reveille is the intersection and confirmation of sulfide at both of the IP anomalies tested in Phase II, namely the G1 breccia target and the Kawich anomaly. The sulfide is hosted in hydrothermally altered and replaced limestone. It generally occurs on bedding plane fractures, with quartz and calcite vein stockworks and hydrothermal breccias developed on major structures and at lithologic contacts.
G1 breccia pipe
- Diamond drill hole RVD21-001 intersected continuous broken ground over 110m through a diatreme-like breccia body. Brecciation overprints all lithologic units. The hole did not determine the bottom; it ended in breccia due to difficult drilling.
- The drill hole contains 2.4m @ 30.7 g/t silver, including 0.61 m @ 97.9 g/t silver.
- The hole was terminated in breccia, with 0.61 m @ 11.75 g/t silver at the bottom.
- There is a strong correlation of silver to the high temperature base metal signature of copper-moly-tungsten at G1, and also the correlation to the sulfide alteration signature of arsenic-antimony.
- The is an introduction of hydrothermal gold into the G1 breccia pipe over a length of 42 m; it correlates with, but overprints and extends beyond the polymetallic interval with silver.
- Introduction of hydrothermal gold is also evident over a 90m interval in the RC hole RV20-006, with a maximum of 176 ppb gold over 5ft, and above detection limit in nearly the entire hole. Hole 6 targeted the roots of the G1 breccia body approximately 130 m to the west of diamond drill hole RVD21-001 located on the ridge.
Kawich IP anomaly and Pyrite Alteration Zone
Two holes were completed on the Kawich IP anomaly. Both holes achieved depths of around 450 m, and both intersected >150 m intervals of sulfide, starting at 120 m depth, which was the modeled depth-to-top of the IP anomaly. Altered but relatively impermeable volcanic flows cap the intersections and are clearly an important aquitard and focusing agent to the mineralizing fluids. The sulfide stringers, semi-massive seams and disseminated grains are hosted in black, de-calcified and dolomitized lime mudstone of the Devil’s Gate Formation, for which neither drill hole crossed the lower contact.
- There is a strong correlation between silver and the high temperature base metal signature of copper-moly-tungsten, and also to the sulfide alteration signature of arsenic-antimony.
- Hydrothermal gold is introduced over approximately 40 m of core in RC drill hole RV20-007, from 167 to 301 m, with up to 28 ppb Au. It is associated with secondary pyrite alteration hosted in dark grey, decalcified lime mudstone. Gold also occurs in the basal part of overlying Tertiary volcanic cover, which served as a fluid cap to the fluid system and is thus pervasively altered.
- There is a high temperature vector in geochemical data, for example, molybdenum, which increases from the western flank of the range towards the Kawich anomaly in the covered valley. The same vector is evident in alteration mineral data obtained from the continuous hyperspectral scanning of each drill hole, in its entirety. For example, there is an increase in high temperature potassium clay minerals from the western flank of the range towards Kawich.
Kawich was not explored during the previous 140 year history of prospecting in the district, yet this drilling confirms its potential as a gold-fertile porphyry center and overall driver of the polymetallic mineral system at Reveille.
Going Forward in 2022
The Company will fully integrate and fully interpret an extremely large data set from the continuous geochemical sampling and hyperspectral scanning of all nine drill holes completed in 2021 in order to formulate the right plan for follow-up drilling in 2022. We anticipate the focus to be on the large, gold-bearing pyrite alteration system at Kawich given its sheer size, and the clarity of the high-temperature geochemical and hyperspectral mineral vectors towards Kawich which are already evident from the first-pass analysis of the data.
In the meantime, the property was expanded in the summer of 2021, both westward to cover the entirety of the Kawich target area, and eastward to cover an EM conductor named ‘Big Apple” that was discovered by our high resolution airborne EM survey completed in 2020. There is no previous exploration in the area of Tertiary volcanic cover, and it is targeted for a buried, high grade copper-silver manto analgous to the historic Reveille South mine located to the southwest at the south end of the Reveille range. Big Apple is the single-strongest conductive feature in the entire survey block from 2020. VR will integrate data from mapping and rock and soil sampling completed in September, 2020, to refine the EM target at Big Apple and include it in the prioritization and planning for follow-up drilling at Kawich in 2022.
The Reveille property is located in the southern part of the Walker Lane mineral belt in Nevada, host to numerous Tertiary-aged epithermal gold and silver deposits with production spanning some 160 years, from the days of the Comstock lode at Virginia City in 1860 to the giant Round Mountain deposit and heap leach mine operation today.
Like Comstock, Round Mountain and many other precious metal deposits in the belt, Reveille is associated with Tertiary-aged, rhyolite volcanic centers. The property occurs in a setting of nested calderas; it is on the western margin of the Goblin Knobs Tertiary volcanic center where it is disrupted by the resurgent growth of the Kawich caldera to the southwest.
The Reveille mineral system is hosted within a sequence of generally west-dipping and locally folded Paleozoic stratigraphy in contact with the Goblin Knobs Tertiary volcanic rocks on the eastern side of the property. The stratigraphy comprises Ordovician Eureka Formation quartzite and overlying Ely Springs Formation limestone with interbedded with chert and mudstone which are in turn overlain by the massive regional dolomites of the Devonian Nevada Formation that dominates the topography of the south Reveille range and the property. A carbonate stratigraphy dominated by densely compacted and commonly fissile, finely laminated, dark grey, organic-rich fossiliferous lime mudstone of the Alamo Formation, also Devonian in age, overlies the Nevada Formation dolomites on the western side of the property and western flank of the range, and is potentially an important aquitard for mineralizing fluids because most of the showings exposed at surface at Reveille occur in the Nevada Formation dolomite at or near the contact with the overlying mudstone.
Silver-copper mineralization at Reveille occurs in vein stockworks, manto’s and breccia bodies hosted in the Paleozoic carbonate rocks at the western margin of Tertiary Goblin Knobs caldera. The Nevada Formation is completely altered to coarsely crystalline hydrothermal dolomite in proximity to all of the showings at or near the overlying contact with the Alamo Formation mudstone. Mineralization is focused along the intersections of bedding and vertical fold limbs along north-easterly trending fold axis. At a larger scale, a regional north-trending extensional fault crossing the western part of the property and coincident with ring faults which bound the western boundary of the caldera appear to form the deeply seated structural root which accommodated the volcanism and CRD mineral fluid systems at Reveille.
Reveille has both scale and intensity:
- Hydrothermal dolomitization extends across the entire 2 x 3 km property at Reveille;
- Both the vertical and lateral dimensions of the individual silver showings are large;
- There is complete hydrothermal dissolution and replacement of limestone in breccia pods and pipes, there are spider-networks of quartz veinlets in completely recrystallized dolomitic limestone, and feeder vein and breccia pod occurrences with red-brown silica cement have very high concentrations of both silver and copper.
A brief summary of new data highlighting the character and potential of the main showings themselves, and the overall silver-copper CRD mineral system at Reveille includes:
- 6 different showings with historical workings on vein and/or breccia mineralization containing > 100 g/t silver and 1% copper;
- 600 g/t silver and 0.7% copper at Silver Ace showing, with more than 300 vertical metres of topographic extent to hydrothermal replacement mineralization between Silver Ace on the ridgetop and Lincoln showing below;
- 2,600 g/t silver and 1.4% copper at Lost City and 2,200 g/t silver and 1.2 % copper at Lincoln on the west side of the property, which provide a potential vector to the heart of the overall CRD mineral system at Reveille;
- 1,500 m lateral extent of west-dipping, stratigraphically controlled high-grade silver mineralization between Zebra and Spade zones.
Silver Ace showing. Metre-scale breccia pipes with associated quartz vein stockworks occur within completely altered limestone at the Silver Ace and Saddle showings, where quartz veins observed at surface up to 2 m wide contain coarse-grained freibergite, with silver-bearing tetrahedrite also disseminated in altered limestone country rock. High grade silica replacement with 0.45% copper and 1,535 g/t silver in a fold hinge 100m above the Silver Ace showing and 400 m above the high-grade silver-copper replacement pods, feeder veins and and hydrothermal shatter breccia at the Lincoln Gulch showing in the valley below.
Lincoln – Lost City showings. A series of replacement pods, feeder veins and vein breccia and hydrothermal shatter breccia cemented by red-brown silica with disseminated freibergite and high concentrations of both silver and copper, including 2,200 g/t silver and 1.2 % copper in shatter breccia at Lincoln, a copper rich feeder quartz vein and replacement pod with 1.43% copper and 1,420 g/t silver in altered dolostone at a newly discovered showing below Lincoln, and 2,660 g/t silver and 1.52% copper in a silver and copper-rich replacement pod and goassanous feeder breccia at the Lost City showing, all on the west side of the property.
A sample of intensely altered quartz-eye porphyry containing 0.5 g/t silver, invaded by quartz veinlets and completely overprinted by sericite alteration is a rock type and alteration style that is a potential vector to the overall igneous driver and large-scale exploration target for the heart of the CRD hydrothermal silver-copper mineral system at Reveille.
Zebra – Combo showings. A breccia body at Pete has a continuous chip sample with 320 g/t Ag across 12 m. The fluid history at Zebra is dynamic: both the fragments and the matrix of the breccia are altered, and there are local mantos of massive, zebra-textured replacement and mineralization. Similar to the area of Lincoln – Lost City showings, grab samples of breccia or vein with red-brown silica cement have the highest concentrations of silver, which are up to 1,000 g/t Ag at Zebra. Overall, there is 1,500 m of lateral extent to the west-dipping, stratigraphically-controlled high grade silver mineralization between the Zebra and Spade zones.
The CRD mineral deposit model (Carbonate Replacement Deposits) unifies the numerous surface showings of high-grade silver in vein stockworks, manto replacement bodies and chimney-style breccia pipes.
Detailed geological mapping completed by VR in 2020 has determined the precise stratigraphic position of mineralization, and importantly the preferred structural controls to hydrothermal fluids. The recently received inversion models for magnetic and EM geophysical data both align with these structural models and identify a new and covered target for the potential core of the CRD mineral system that produced the high-grade silver and copper mineralization exposed at surface in vein stockworks and breccias in the Reveille range.
Further, the Company has defined geochemical and mineral vectors which point westward, to the covered valley west of the range as the potential proximal source area and overall hydrothermal-magmatic driver for the overall district of showings. Evidence for a large-scale magmatic root and/or driver to the polymetallic system at Reveille includes: 1. phyllic alteration mapped in rhyolite tuff both on the northern and eastern margins of the property, and; 2. intensely altered quartz-eye porphyry dykes pervaded by quartz veinlets and completely overprinted by sericite alteration at several showings.
There is a large and prominent magnetic anomaly located in the valley at the southwest end of the structural corridor that controls silver-copper mineralization at the Zebra showing. There is an apparent magnetic-low alteration halo to this anomaly, and its geometry is consistent with the northeast-trending fold axis that defines the structural trend and fluid pathway to the high grade Zebra silver-copper showing exposed in the range. Geochemical vectors for gold, copper, moly’ and tungsten, and for copper/silver and zinc/lead ratios indicate that this magnetic anomaly has the potential to be the proximal, high temperature core to the high grade but distal polymetallic showings scattered across the Reveille range.
Finally, the magnetic, EM and gravity anomalies all occur in the general area where mapped northeast-southwest trending structural corridors, fold axis and/or faults with jasperoid breccia, intersect the north-trending regional-scale extensional fault and coincident caldera ring fault complex at the western margin of the Goblin Knobs caldera and under the western part of the property. This is a deeply seated structural feature that is prospective for hosting a district-scale CRD hydrothermal fluid system driven by a gold-fertile porphyry copper center at Kawich.