Underground Mines & High-Grade Veins at Gold Springs

Why we believe in the huge potential for growth in grade and in resource of our flagship Gold Springs project, located in US, on the border of Nevada and Utah ?

In order for everyone to understand this potential, we want to explain and highlight the information we have on:
1. The History of High-Grade Underground Mines at Gold Springs
2. The Modern Exploration & High-Grade Drill Results at Gold Springs

As we look at these two elements and assess the real potential of Gold Springs, we must never forget to also consider three other key points:

  • The numbers of gold targets can potentially increase                                                                     Today, our 33 gold targets cover only 40% of our nearly 8000 ha. In the remaining 60%, with the help of the recent completed CSAMT ground based geophysical survey, our experienced team still have significant potential to identify new gold targets, even under shallow post-mineral materials.
  • The potential expansion at depth of our existing resources                                                                  The underground historic mines operated near the surface at shallow depth and our existing resource is only at an average depth of 130 meters. The CSAMT ground based geophysical survey has demonstrated high resistivity at depth under several of our resources, including North Jumbo, South Jumbo and Charlie Ross.
  • The fact that we are located in one of the best mining jurisdictions in the world                              Gold Springs is in US, on the border of Nevada and Utah, and has all the required infrastructures (water rights, power, roads, railway) and no cultural or environment impediment. This is the perfect place to have open pit and heap leach processing, resulting in low AISC (All In Sustaining Costs) and a profitable operation.

Gold Springs today has a large low-grade gold resource as several high-profile developing resources have: Integra Resources DeLamar project 0.4 g/t, West Vault Mining Hasbrouck project 0.50 g/t, the Black Pine project 0.51 g/t, Gold Standard Ventures Pinion project 0.56 g/t. Low-grade open pit gold operations in Nevada are truly profitable, with low production cost from $850 to $1,150 per oz AISC (All In Sustaining Costs) and a gold price at $1,800 per oz (e.g: Round Mountain 0.53 g/t, Marigold 0.49 g/t, Castle Mountain 0.51 g/t, Mesquite 0.54 g/t, Pan 0.46 g/t, etc.).

Even if we are focused to expand our resource rapidly towards our objective of +3 million oz with a low per ounce discovery cost ($11 in total in 2021), we know that we still have numerous high-grade veins to explore in the future to increase the overall grade with close spaced and deeper drillings that will require more time and money.


The Gold Springs project covers the historic mining districts of Deer Lodge, Fay, and Gold Springs. Gold was discovered in the 1870s when a prospector named Pike found the Etna Vein, in the South Jumbo resource area.

As the districts advanced, many mines were opened on high-grade veins carrying gold grades ranging from 6 g/t to over more than 20 g/t gold. These underground mining operations were developed using simple technics, from the surface to a shallow depth of 30 to 70 meters in general and occasionally up to 180 meters.

The town of Gold Springs was established in the late 1890’s and it was not until the discovery in 1896 of gold and silver high-grade veins in the Stateline district, 20 kilometers to the north, that a great number of prospectors were attracted to the area. Mining began in 1897 and continued intermittently until 1942, when it was shut down due to World War II.

At Gold Springs, underground mines have historically
exploited high-grade gold veins to a shallow depth

At least 14 underground mines, numerous historical workings and 4 mills to process the ores were developed on 28 of our 33 existing Gold targets.

6 Historic mines were in operation on our 6 existing resources:
- Etna (South Jumbo) 0000000000000000 Charlie Ross
- Jumbo  00000000000000000000000000 Thor
- Great Eagle 00000000000000000000000White Point

8 Historic mines were in operation on our existing targets:
- Midnight 0000000000000000000000000 Jennie Extension
- Snow 000000000000000000000000000  Iris
- Homestake 00000000000000000000000 Independence
- Declaration 00000000000000000000000 Horseshoe Extension

In the 19th and early 20th century, exploration targeted only high-grade veins, as the gold price was around $20 per ounce. Exploration techniques consisted of combing the hills, looking for veins, crushing the rock and panning for colors of gold. Once it was determined that the vein was gold bearing, a pit was dug to determine if sufficient gold was present to be mined at a profit.

In the early 20th century, ore was extracted by hand using picks, shovels, tracked ore carts and steel hand hammers for drilling. Later, steam was used to power the drilling equipment, but the work was still labor intensive. This made building a mine long and complicated, especially to extend it deeper with sufficient safety.

The processing to capture gold at that time was done in general through a gravity separation process, but mills at Gold Springs used vat cyanidation to capture additional gold.

All these historic underground mines have demonstrated
these high-grade veins are an important part
of the mineral systems at Gold Springs


North Jumbo - M&I Resource of +402,000 oz AuEq (with Tremor)
North Jumbo has several historic tunnels, shafts, pits and a production reported to be from narrow high-grade veins over a limited strike length of 30-50 meters. A previous operator conducted underground sampling of the Jumbo Vein over a length of 33.5 meters and 8 samples averaged 3.61 g/t gold equivalent. That same group excavated trenches across the Jumbo Vein in the central portion of the North Jumbo resource, which returned the following results:
- 22.82 g/t gold equivalent over 1.4 meters*;
- 07.66 g/t gold equivalent over 1.7 meters*;
- 04.79 g/t gold equivalent over 1.4 meters*;
- 03.95 g/t gold equivalent over 1.5 meters*;

In 1974, another group drilled 3 holes into the Jumbo vein system with these results:
- 07.17 g/t gold equivalent over 3.04 meters* in hole J-1
- 03.96 g/t gold equivalent over 3.04 meters* in hole J-2.

* Numbers are presented as historical context and not in compliance with 43-101 and are estimated true thickness.

South Jumbo M&I Resource of +243,000 oz AuEq
The Etna mine on South Jumbo was an important gold producer from 1938 through 1942. The Mine development consisted of a shaft, two levels, numerous pits and three winzes joining the 30 and 53 meter levels. The Etna Vein was mined through an incline shaft with 80 meters of tunneling, 30 meters below surface.

In outcrop, the vein appears as a zone of small quartz and calcite stringers coalescing into a single 3 meter wide vein underground. Etna is a complex system of innumerable, quartz-carbonate veins and stockwork zones that can be traced for more than 700 meters along a ridge.

In 1976, Lee Perry published a geology report on the Gold Springs District. Perry conducted sampling across the district, including the Etna Vein from the shaft which returned 6.81 g/t gold equivalent over 1 meter. A sample of the Etna Vein taken from a pit 46 meters to the south returned 23.81 g/t gold equivalent over 1.5 meters.

In the 1980s, a company completed a series of trenches across the Etna Vein over a distance of 21 meters and the sampling returned with the following results:
- 06.46 g/t gold equivalent over 1.7 meters;
- 06.03 g/t gold equivalent over 2.0 meters;
- 03.74 g/t gold equivalent over 1.4 meters;

That same company completed 2 holes in the South Jumbo resource which returned high-grade intercepts:
- 09.60 g/t gold equivalent over 10 meters in hole E88-1 and
- 02.68 g/t gold equivalent over 05 meters in hole E88-2.

Grey Eagle M&I Resource of +166,000 oz AuEq
Three adits were developed to explore the Grey Eagle Vein, that can be traced for 640 meters along a general north-south strike. The north end of the structure is composed of quartz stockworking and veining in zones up to 137 meters in width.

Two tunnels were driven under the area where GRC drilled the initial discovery holes at Grey Eagle which returned 6.39 g/t gold equivalent over 19.8 meters. Previous work at the Grey Eagle by Energex in the 1980s included underground sampling from these tunnels with the following results (pre 43-101):
- 12.5 g/t gold over 3.50 meters 00000011.6 g/t gold over 0.91 meters
- 10.3 g/t gold over 0.91 meters 00000009.7 g/t gold over 0.91 meters
- 06.3 g/t gold over 1.83 meters 00000006.3 g/t gold over 0.91 meters.

GRC collected samples from these same underground workings that showed values of up to 29.3 g/t gold and 47.4 g/t silver. These samples are from quartz and quartz-calcite veins, stockwork zones, and matrix-supported breccia cemented by silica.

Charlie Ross M&I Resource of +102’000 oz AuEq (with Pope, Red Light and Tin Can)
The Charlie Ross target includes the Charlie Ross historical shaft and an adit driven to explore the vein structure. Visible gold has been found in rocks from dumps near the open shaft. Historical reports describe a 53 meter inclined shaft with a 12 meter talc zone containing extremely high-grade streaks of gold tellurides and sylvanite with bonanza gold grades.

The Charlie Ross resource is part of an historic mine structural zone that was an important producer with a shaft, 4 levels, 400 meter of drifting and stoping. In 1935 ore reserves reported 4,610 tons averaging 6.25 g/t of gold and 78.1 g/t of silver.

The Pope shaft is the dominant historic working and is estimated to be 75 meters deep. There are numerous slot cuts which were excavated along the vein structures over a strike length of 400 meters that exploited the high-grade gold of this system. GRC sampling of the veins has returned gold values as high as 20.2 g/t and with 88.8 g/t silver. Drilling at Pope in 2012 intersected 9.2 g/t gold over 1.5 meters.

The Red Light target has two deep shafts, one tunnel, and several pits scattered across the target. It is typical to see vein material and strong alteration in the dump materials. The adits at Red light north, south and west were re-opened in 1983, visible gold was observed in dump material which pans well, and massive argillic alteration is present in a shaft and at surface indicating a strong hydrothermal event has taken place. These workings occur in a zone of strong alteration and are approximately on the projected intersection between the Pope Vein and the Snowflake Vein system.

The Tin Can target has numerous pits and one larger adit exploiting the mineralized veins. Samples from the outcropping vein returned 5.2 g/t gold and 61.5 g/t silver.

Thor M&I Resource of +71’000 oz AuEq
Several historic tunnels, shafts and pits are found scattered across the Thor target. The Thor resource is approximately 180 meters west of the historical Jennie Vein. The Jennie Mine was one of the district’s largest producing mines, with a reported grade of 12.4 g/t of gold over widths of 1.5 to 7.6 meters.

The northwest-striking and easterly-dipping vein has been exposed in outcrop and workings for over more than 330 meters. Vein widths vary from 0.8 to over 5 meters. Development on the vein consists of two adits, one shaft, and numerous open cuts. Excavation of the old surface workings, augmented by further backhoe trenching, has unearthed a zone of quartz-adularia veining, with visible gold mineralization within the larger Thor Vein system.

GRC has drilled the Thor Vein and hit several high-grade intercepts, including 5.1 g/t gold equivalent over 6.1 meters. Drilling from 2016 explored the vein system at depth and intercepted a high-grade zone that averaged 45.6 g/t gold equivalent over 7.6 meters, containing 1.5 meter interval that assayed 216.9 g/t gold equivalent.

White Point M&I Resource of +18’000 oz AuEq
The White Point Mine was located along an extensive stockwork structure trending in a northerly direction and was exploited in the early 1900s. Two adits and a shaft were developed on the sheeted gold bearing vein zone +200 meters wide. The mine is credited with at least one ore shipment in 1935 of 37.2 tons grading 17.75 g/t of gold. One GRC sample of the vein assayed 18 g/t gold.

Midnight Target (included in the 2022 drill program)
Historic mine operated in the early 1900s with the deepest shaft in Gold Springs, (estimated at 200 meters) displaying very high-grade veins grading up to 57.3 g/t of gold.

Horseshoe Extension & Homestake Targets (included in the 2022 drill program)
The Horseshoe Mine was a major producer with a reported 39,342 tons with an estimated average grade 10.63 g/t of gold and supported a 100-tons per day mill.

North of the Horseshoe, the north end adit contains approximately 305 meters of workings, with several historical shafts, pits and tunnels to exploit banded quartz-calcite vein systems. The largest historical mine working is a caved tunnel displaying a large dump containing large vein fragments. The Horseshoe and Homestake historical mines were high-grade underground mines that exploited a banded quartz-calcite vein up to 7.5 meters thick. Both these mines are on the same structure.

In 2019, GRC drilled several holes at Homestake on the northern exposure of the vein looking for bonanza grade mineralization near surface with these highlighted results:
- 22.86 g/t gold equivalent over 06.1 meters and with a second wide zone of
- 00.74 g/t gold equivalent over 71.6 meters in hole HS-19-007.
- 04.50 g/t gold equivalent over 03.0 meters in hole HS-19-012.

North Jennie Target
The Jennie mine on the border of Nevada and Utah was the largest producer in the Gold Springs district. The mine consisted of the Jennie Vein traced over more than 180 meters with a width of 1 to 2 meters, just east of the Thor Vein, with 100 meter shaft, 4 production levels and with stopes up to a 6 meter width. Free gold occurs with quartz-adularia gangue, some calcite and occasionally barite.

Utah Mining commenced development at the turn of the 20th century, but production was first reported in 1907 and lasted until the 1940s with an average grade of 7.45 g/t gold equivalent.

Iris Target
The historical Iris mine consisted of a shaft estimated to be roughly 180 meters deep, two adits and several pits and trenches. Samples from old stockpiles of ore return gold grades of 38.09 g/t.

The main vein forms a subdued outcrop pattern which can be traced for 240 meters along a north-northeast strike and steep easterly dip. The vein is composed of a quartz and carbonate stockwork network. The Iris trench 75 meters to the north of the Iris shaft was sampled by GRC and averaged 9.27 g/t gold and 16.22 g/t silver along a 20 meter length.

Declaration Target
The quartz vein at Declaration is a continuation of the Independence Vein, which features extensive historic workings. There are several shallow shafts and pits along the exposed strike length of the vein. GRC sampling of the vein has returned values as high as 10.23 g/t gold equivalent.

Fluorite Target
Hosted within the Bull Hill rhyolite intrusive plug, a 0.6 to 0.9 meter wide vein of purple and green fluorite and hematite has been explored through a shaft and an adit with some 275 meters of drifting.

Sampling 25 feet below the collar of the shaft conducted by Perry in 1976 showed the veining contained gold values including 2.66 g/t across 0.6 meter. A grab sample assayed 13.45 g/t of gold for the shaft dump. GRC samplings returned gold values as high as 32.45 g/t with several other samples over 10 g/t.

Gold equivalent based on US$1,800/oz gold, US$25/oz silver and 50% for silver recovery. True thickness is estimated to be 70-100% of reported length.

Other GRC Targets with historical workings:

  • Snow: Several historical slot cuts and one mine shaft focusing on the structural zone, quartz-calcite veins, breccias and stockwork veining.
  • Horsetail: Much of the area is covered by post-mineral gravels, but in the uncovered area an adit and shaft exploited a 0.5-meter-wide light-green, banded quartz-calcite vein similar to those seen at the historic Horseshoe mine.
  • Central Jumbo: Numerous shallow shafts, trenches, and pits which exploited the veins within the Central Jumbo target.
  • Juniper: Numerous historical mining pits and one reclaimed shaft.
  • Gem: Numerous historic workings located on both the north and south sides of the Gold Springs Wash.
  • West Ridge: Numerous prospect pits and two adits exploiting the mineralized veins and stockwork material.
  • Big Summit: Several prospect pits with one deep shaft situated along the southern edge of the target.
  • Camp Bell: An adit and few historic pits.
  • Fitch: Few historical mining pits and trenches and one reclaimed shaft.
  • Lost World: Few small historical prospect pits.
  • Pinyon West (Pinyon North): An adit and shallow surface workings, such as pits and trenches.
  • Pinyon (Pinyon South): Scattered pits and cuts.
  • Ridge: Several small prospect pits.




Modern exploration emerged to the districts in the 1980s as gold prices surged to over $600/ounce. Exploration techniques have evolved from the old prospecting days to incorporate advances in technologies. The modern exploration often starts through data compilation from historical reports and publications to initially focus on the ground search. This step is followed by a work integrating advanced technologies, as satellite imagery, airborne magnetic and electro-magnetic surveys, ground based geophysical surveys which can detect types of alteration associated with different deposit types, Lidar which generates precise three-dimensional information. These images are also used for a first pass structural interpretation to further focus the search. Once that is completed, a ground search is carried out with geologic mapping and sampling for gold. If a target is identified, geophysical methods can be used to look at subsurface features which can help guide the drilling program (reverse circulation and diamond core drill) which ultimately determines if there is an economic deposit.

All of these methods are being used at Gold Springs
to develop a gold resource of +1 million ounce,
to direct our drilling to expand it and
to make new discoveries.


Open pit mining today allows large and low cost operations to depths of over 500 meters. The development of heap leach technology to treat low-grade ores allows for excavating large volumes of material at extremely low costs. Material is placed on large pads and subjected to leaching by dilute cyanide solutions which extract the gold and silver. This processing method allows for large scale surface mining verses the narrow underground mines of the past, reducing costs and allowing for exploitation of low-grade ores. Low-grade open pit gold operations in Nevada are truly profitable, with low production cost from $850 to $1,150 per oz AISC (All In Sustaining Costs) and a gold price at $1,800 per oz (examples: Round Mountain 0.53 g/t, Marigold 0.49 g/t, Castle Mountain 0.51 g/t, Mesquite 0.54 g/t, Pan 0.46 g/t, etc.).


Historic mining at Gold Springs have demonstrated the existing of high-grade veins and high grade gold production. Many of our drilling results have also returned high-grade results, as you can see on the following table, and we still have numerous undrilled targets with high-grade historical results. These three elements combined demonstrate that we will still have numerous high-grade results in the future to increase the overall grade with close spaced and deeper drillings.

in Gold equivalent (AuEq)
   North Jumbo Resource South Jumbo Resource:
119.34 g/tover1.5 meters 22.36over1.5 meters
30.90 g/tover 4.6 meters 10.81over4.6 meters 
 9.08 g/tover1.5 meters 8.35over6.1 meters
8.79 g/tover1.5 meters 7.46over1.5 meters
8.42 g/tover3.1 meters 7.36over3.1 meters 
6.87 g/tover24.4 meters 5.47over19.8 meters
6.09 g/tover 3.1 meters 4.36over10.7 meters
4.86 g/tover 3.1 meters 4.28over3.1 meters
4.59 g/tover3.1 meters 3.68over4.6 meters
4.46 g/tover1.6 meters 3.50over3.1 meters
4.41 g/tover3.1 meters 3.44over3.1 meters
4.35 g/tover1.5 meters 3.25over4.6 meters
3.68 g/tover12.2 meters  
Grey Eagle Resource Thor Resource:
11.69 g/tover1.5 meters 45.61 g/tover7.6 meters
6.00 g/tover19.8 meters 5.54 g/t over6.1 meters
5.33 g/tover3.0 meters 5.12 g/t over6.1 meters
5.07 g/tover3.0 meters 4.86 g/tover3.1 meters
4.29 g/tover10.7 meters 4.79 g/tover3.1 meters
4.11 g/tover7.6 meters 4.24 g/tover6.1 meters
4.00 g/tover3.0 meters  
3.33 g/tover4.5 meters Homestake Target
3.28 g/t over12.2 meters 22.84 g/tover6.1 meters
3.14 g/tover9.1 meters  
2.97 g/tover4.5 meters 

Gold equivalent based on US$1,800/oz gold, US$25/oz silver and 50% for silver recovery. True thickness is estimated to be 70-100% of reported length.

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