New Boston epitomizes the Company’s blue-sky exploration strategy of applying new exploration technologies and modern mineral deposit modeling to large-footprint yet underexplored porphyry copper systems in Nevada. The company will leverage the experience gained from exploration on its Bonita and Junction properties located in north-central Nevada to advance the large and fully zoned, porphyry-skarn-breccia system exposed on surface at New Boston.
Nevada has both history and pedigree in the world of porphyry copper and moly. New Boston is located in a long and well-established belt of Cretaceous-aged porphyry systems that runs northwest-southeast in west-central Nevada. It is located between the past-producing Yerington porphyry copper camp located approximately 100 km to the northwest, and the Cretaceous Hall moly-copper deposit located approximately 100 kilometres to the southeast.
The polymetallic skarn and porphyry mineral system comes to surface at New Boston. Mineralized sheeted and stockwork veins occur in both quartz monzonite stocks and dacite porphyry dykes, and in country rock Paleozoic limestone over a strike length of approximately 4 kilometres.
Artisanal mining at the turn of the century focused on high grade copper veins at the Blue Ribbon mine at the west end of the 4 km system. Sheeted and stockwork quartz veins with copper and moly in porphyry-style mineralization related to swarms of sheeted monzonite dykes at Jeep Mine in the central part of the system was the focus of exploration starting in the late 1960’s and extending to 1981. Finally, there was a brief period of exploration drilling in the mid-1980’s for shallow, skarn-related tungsten mineralization on the western flank of Jeep Mine.
But it was the expert porphyry exploration teams of Bear Creek, and the mineral divisions of Gulf and Conoco, which were common in big oil companies in that era who really put New Boston on the map. It was Conoco in particular who logged the miles in the field over nearly a decade to both recognize and outline the geology, alteration and mineralization across the entire porphyry – skarn system at New Boston throughout the 1970’s. However, that exploration came to an abrupt stop in 1981, as it did across much of North America for that matter, in response to a global collapse in the commodities sector, which in turn seeded the exit of petroleum companies from the minerals and mining sector.
A central porphyry stock was inferred by Conoco for the system of mineralized sheeted veins they mapped on surface at New Boston, but it was never identified nor drilled prior to the collapse of their exploration. Further, their work did not include systematic and modern, multi-element ICP-MS geochemistry on either surface samples or drill core in order to determine the polymetallic grade potential of the large-footprint hydrothermal-magmatic porphyry system in copper, moly and silver.
VR’s goal is straight forward: to simply finish the expert-level porphyry exploration which began in the 1960’s at New Boston but ended abruptly in 1981, incomplete and never re-visited. The opportunity for VR is twofold:
- To use state-of-the art exploration geophysical technologies that were literally not available in the 1970’s to identify targets for drill testing for a central porphyry stock which acted as a driver and metal source for the sheeted veins exposed on surface along a 4 km strike, and;
- To use modern, ICP-MS trace element geochemical techniques to define the grade potential of the polymetallic system for copper and silver at New Boston, in addition to the world class attributes in both grade and thickness for molybdenum that is demonstrated in numerous drill holes completed by Bear Creek and Conoco.
VR received its first NOI drill permit from the BLM for New Boston in October, 2023. VR then completed a site visit to New Boston in November; a short field video with the VP Exploration is available on this Project Page. The purpose of the trip was to meet with potential drill contractors in person, in the field, to discuss the logistics for the first-pass drill program planned for the East Zone conductor in Q1 2024.
The proximity of New Boston to state HWY 95 provides tremendous logistical advantages for drilling and advanced-stage exploration, as shown on several maps provided on this Project Page.
Why now? The US government recently added copper to the top of its Critical Metal list for domestic, raw material supply for sustainable, downstream technologies and industries as the Green Transition emerges (August, 2023). Nevada has both a long history in mining and a well-established pedigree and endowment in copper, and we believe that New Boston has both the size and the polymetallic grade composition to contribute to that ongoing legacy.
In summary. Conoco developed a 3.14 BT geological model to encompass the mineralized sheeted veins at New Boston, exclusive of a central porphyry stock that was inferred at the time but never identified nor drilled - but technology matters – and some forty years after the exploration and reconnaissance drilling by Bear Creek and Conoco came to an end at New Boston, new geophysical technologies not available at that time, including both multi-sensor gradient magnetics and 3D array DCIP surveys now provide clear targets for concentrated vein stockworks with conductive copper sulfide at the centre of the large-footprint porphyry system of sheeted veins exposed on surface.
We believe that we can build on that large volume geological model by intersecting and confirming the presence of a central porphyry stock with a concentrated vein stockwork with conductive copper sulfide; the ultimate source and driver for the system of sheeted veins exposed on surface over a 4 km strike length.
The New Boston porphyry-skarn mineral system comes to surface. Stockwork and sheeted quartz veins in both quartz monzonite plugs and dykes and in country rock Paleozoic limestone are exposed on surface over a strike length of approximately 4 kilometres (see field photographs attached to this Project Page).
VR has the experience in Nevada and expertise in mineral exploration to advance New Boston. Work done to date includes:
- Integration of all regional geoscience data available for the area with all historic exploration data for New Boston obtained during the acquisition of the property;
- Structural mapping of vein and dyke geometries across the entire property, summer 2022, and select vein sampling for geochemical zonation in the summer of 2023.
An airborne magnetic and radiometric survey was completed in April 2023. It was contracted to Precision GeoSurveys Inc. to utilize its exclusive, multi-sensor gradient technology and three-boom design to collect high resolution magnetic data in real time for enhanced subsurface interpretations in three dimensions, in addition to collecting VLF-EM and radiometric data. Survey design on the 3 x 5 km block for high resolution data includes 75 m line-spacing and completion of 8 additional tie lines for 241 line-kms in total, with an average flight altitude maintained at just 35 metres above ground.
Also in the spring of 2023, VR completed a ground-based 3D IP geophysical survey completed in April by DIAS Geophysical Limited using its proprietary DIAS32 DCIP technology and grid array of transmitter and receiver stations with real time radio frequency data collection. An equant grid of 200 metre–spaced stations over a survey block 1.6 x 2.2 km in size covers the 2,100m strike of sheeted veins exposed on surface in the central part of the porphyry system exposed on surface in the western part of the property. The survey generated more than 80,000 data points for inversion modeling and resultant 3D models of chargeability and resistivity.
The results of the modern DCIP, magnetic and radiometric surveys completed in April, 2023, were announced on June 26, 2023. Two geophysical plan maps with accompanying cross-sections are provided as stand-alone figures on this Project Page. Highlights include:
IP anomaly: 15mV/V, 950 m long, from surface to 500 m depth and open, which outlines the target for a mineralized porphyry intrusion below the
Jeep Mine in the western part of the system of mineralized sheeted veins exposed on surface over a 2,100 m strike length. Note:
- New Boston is a low-pyrite system, so the core IP iso-shell at 15mV within a 12 mV halo is consistent with a base metal sulfide concentration.
- The IP anomaly at depth corresponds to increasing conductivity, below the surface expression of the Jeep Mine hill;
- Drill hole NB-4 with 992 ft @ 0.08% MoS2 is located north of the conductivity core at depth in the center of the large IP anomaly.
- Conductivity anomaly: high amplitude, 900 m long, from surface to 500m depth and open, which outlines the target for a high temperature, mineralized porphyry-skarn center at East Zone in the eastern part of the system of sheeted veins at New Boston. Note: 1. The high amplitude of the conductivity anomaly indicates concentrated sulfide minerals; 2. Drill hole NB-1 with 318 ft @ 0.14% copper and 0.08% moly is located at the eastern end of the conductivity anomaly; 3. The conductivity anomaly correlates with high temperature potassic alteration index in soil geochemistry, and potassium enrichment indicated by the airborne magnetic and radiometric survey, and; 4. The conductivity anomaly is inferred to be the source to the quartz veins with copper exposed on surface at CCT Zone;
- GW boundary zone: the GW boundary zone separates the large IP anomaly targeted as the porphyry center below Jeep Mine from the high amplitude conductivity anomaly at East Zone which is targeted as the mineralized porphyry center feeding the copper veins exposed on surface at CCT Zone. It is based on geological mapping and sampling by VR, and is supported by the new data derived from the magnetic, radiometric and DCIP geophysical surveys in 2023. It is itself mineralized; it forms a continuous gossan zone with quartz veins and quartz vein stockworks with limonite and copper wad after massive chalcopyrite (copper sulfide), and silver values of up to 112 g/t in surface grab samples. The structure follows the topographic high of Jeep Mine hill where marbelization of limestone is strongest but copper veins at surface lessen with topographic elevation on the hill; however, copper is evident in both modern ICP-MS soil geochemical data, and in the new anomalies from the DCIP survey.
Overall, the new ground DCIP conductor at East Zone has been given top priority based on its size, its proximity to known copper mineralization which is the strongest of any mineralization seen across the property spanning the entire 4 km strike of the polymetallic sheeted vein system, and because there are not historic drill holes in the target, ever, period. Supporting attributes of the East Zone conductor (EZ) include:
- Copper at surface. The core of the conductor comes to surface into a patch of maroon-coloured soil amongst hematite skarn and intense quartz vein stockworks, with up to 0.8% copper in soil;
- Copper Intersections. A 2010 drill hole located 300m to the south of the conductor, up-dip in limestone, intersected 279ft @ 0.24% Cu from 12ft depth, coincident with a small conductor;
- Strike length. Starting from the maroon soil surface expression, the EZ conductor extends 900 m to the northwest on plan map, and converges with the Jeep Mine conductor at depth (Figure 3);
- Open to depth. The EZ conductor plunges from surface through the 500 metre depth extent of the 3D voxel model; amplitude strengthens and volume increases with depth, and is open.
A first pass drill program of 3 – 4 holes for approximately 2,500 metres is planned for the East Zone target in Q1, 2024.
For strategic reasons, two separate NOI permit applications were prepared to cover both the large IP chargeability anomaly at Jeep Mine and the large conductivity anomaly at East Zone (EZ), respectively. The conductivity anomaly at East Zone is the priority and, as such, its NOI permit was submitted first and was approved and received by the Company in October, within the standard 15-day timeframe conveyed by the BLM. The Jeep Mine NOI application has been similarly prepared for submission and timely approval.
The new conductor at East Zone offers the potential to discover a mineralized porphyry stock that is the source of the system of mineralized, sheeted quartz veins exposed on surface over a 4 km strike. Why?
- There are bona fide polyphase stockwork vein geometries of quartz with copper sulfide, at surface;
- There are bona fide dacite porphyry dykes together with quartz monzonite stocks, at surface, and;
- There are bona fide high temp. potassic alteration mineral assemblages with biotite and magnetite.
Modern ICP-MS geochemical techniques will be used on continuous sampling of drill core. The goal is to intersect high temperature base metal sulfide assemblages in a porphyry stock (s) central to, and sourcing, the large footprint system of sheeted and stockwork mineralized veins exposed on surface at New Boston. The modern geochemical data will also provide the first systematic evaluation of the grade potential of the polymetallic system at New Boston for both copper and silver, in addition to the well-established endowment in moly.
New Boston is located in Mineral County, approximately 150 kilometres southeast of Reno, Nevada.
The property location affords both year-round and cost-effective exploration. Access is from the nearby town of Luning located just 5 km to the northeast, on HWY 95. The property itself is criss-crossed by a myriad of old trails and roads, reachable from the highway.
Topography at New Boston is dominated by the Garfield Range; ridge lines are gentle but scree slopes are common. Overall, outcrop is extensive and vegetation is sparse at New Boston. Where outcrop is covered, colluvium is interpreted to be thin and local in nature.
Climate is semi-arid to arid, with hot dry summers and cold dry winters.
The New Boston property is large. It consists of 77 claims in one contiguous block covering 583 hectares (1,441 acres). It covers the entire mineral system and its inferred down-dip potential east of the westernmost skarns at Blue Ribbon.
The property is on federal land administered by the Bureau of Land Management (BLM). There are no state or federal land use designations, or privately-owned land which impedes access to the property, nor is the property within the BLM’s broadly defined area of sage grouse protection.
The property is owned 100% by VR. There are no underlying annual lease payments, nor are there any joint venture or back-in interests. The property vendor retains a royalty on the property, with a buy-back provision to VR.
The New Boston property is located in the Walker Lane structural belt and mineral district in west-central Nevada. The Walker Lane is transtensional in nature, related to right-lateral movement along the western margin of North America in Tertiary time. This grain is discordant to the dominant northeast grain of the Basin and Range extensional structures dominant to the east and north throughout Nevada.
Published ages on the quartz monzonite stock at New Boston range from 72 to 82 Ma (late Cretaceous), consistent with the age of other nearby porphyry deposits such as Hall. Collectively, they are the result of transpression and crustal extension which developed along the western margin of North America following convergence and related subduction through the early Mesozoic.
The oldest rocks exposed in the Garfield Range are a late Paleozoic marine succession of limestone and shaled, commonly mapped as slate and marble. Permian mafic volcanic rocks occur at the top of the succession south of the property.
Deformed Paleozoic strata at the property are overlaine by the Triassic Luning Formation. The shallow marine succession generally strikes east-west and dips moderately to the north. The shallow marine sequence of locally algal limestone is intercalated with crystal tuff, coarser lapilli tuff and tuffaceous siltsone which underlay limestone in the southern prat of the property, and argillite mudstone which overlies the limestone in the northern part of the property. The Jurassic Dunlap Formation is present south of the property, consisting of maroon siltstone and pebble conglomerate which have a “red bed” appearance overall. In this location, the Luning Formation strata have been thrust over the younger, north-dipping strata of the Dunlop during a late Mesozoic, south-vergent compressional event.
A central valley extensional fault, east-block down, bisects the middle of the property. It strikes north and is a low-lying area of pediment cover in between exposed ridges of colluvium on exposed, broken outcrop with little vegetation which is characteristic of most of the Garfield range. This late central valley fault at New Boston accommodated the extrusion of intermediate volcanic rocks including flows, tuff and breccia in the Pliocene.
The property itself is underlain by the Triassic Luning Formation, consisting of limestone with interbedded felsic tuff and argillite, which have been thrust over Jurassic redbeds of the Dunlap Formation to the south. The Luning Formation is intruded by numerous quartz monzonite porphyry dykes and sills of presumed Cretaceous age.
Monzonite and quartz monzonite plugs and concordant dykes intrude the Triassic limestone succession across a 4 km breadth east-west on the property. Monzonite is pink weathering, and medium grained, dominated by mm-scale plagioclase and cm-scale orthoclase phenocrysts. Quartz phyric textures in lighter weathering dacite porphyry are evident on the east side of the property. Colour index in both rocks is very low, biotite is the primary mafic and magnetite is generally absent. Radiometric age dates from 1979 using K-Ar systematics on hornblende and biotite in quartz monzonite range from 79 to 82 Ma (late Cretaceous), respectively.
Alteration in country rock limestone ranges from patchy marbelization to wholesale recrystallization across the entire 4 km breadth of sheeted veins on the property, with wollastonite, garnet and diopside in vein assemblages at Jeep Mine and at East Zone. Clay alteration of the tuffaceous unit is evident at CCT Zone and farther South at Kay Mine, with copper oxide after copper sulfide in disseminated clots and decimeter-scale veins of quartz.
Pre-existing Paleozoic and Mesozoic fold and fault structures localize hydrothermal fluids and mineralized veins related to emplacement of the monzonite stock into the deformed early Mesozoic limestone stratigraphy in Cretaceous time.