Heliostar is a Vancouver based junior exploration company focused on high-grade gold exploration in North America:
Heliostar’s 100% owned Unga Project on Unga and Popof Islands in Alaska’s Aleutian Islands, is an under-explored district. The islands sit near the center of the Alaska Peninsula, about 900 kilometres southwest of Anchorage, Alaska. Prospectors discovered gold on the southeast side of Unga Island in the 1880s. Two mines, the Apollo gold mine, and the Sitka gold mine operated between the late 1880s and the early 1920s. Alaska’s first underground mine, the Apollo mine, produced around 100,000 to 130,000 ounces of gold. Historical reported gradefor the production ranged from 7.5 grams per tonne (“g/t”) to 13.7 g/t gold The Unga Project holds more than 35 gold, silver, and base metal occurrences. Heliostar has prioritized four primary targets for exploration: SH-1, the Apollo Sitka Trend, Aquila and Centennial. The Apollo-Sitka trend was host to Alaska’s first underground gold mine (the Apollo-Sitka mine, 1886-1922). The company focused on those four targets with its 2020 drilling program and achieved outstanding results. The company will focus on these targets in 2021 while advancing additional targets to the drill testing stage.
SH-1 is a priority target at Unga. It holds a high-grade inferred resource with 384,318 ounces gold at a grade of 13.8 g/t and has significant potential for expansion with high grade intercepts open along strike and at depth. This resource focuses on the Main Shoot with tightly spaced drilling, but widely spaced drilling outside of the Main Shoot leaves gaps in the company's understanding.A 100-metres vertical gap existed between surface and the shallowest vein intercepts. In 2020, the company completed seven drill holes to improve the company’s understanding of the rocks around the uppermost portions of the Main Shoot. These holes were 50-metres step-outs from previous drilling. Based on
earlier drilling, it was possible to interpret both steep and shallow rakes to mineralization but holes SH20-02 and SH20-03 suggest a steeper orientation is more likely and this will guide drilling in 2021.
· 7.74 (g/t) gold and 27.0 g/t silver over 11.65 meters (m) from 12.95 m downhole including;
· 16.06 g/t gold and 37.7 g/t silver over 4.0 m from 12.95 m downhole
· 18.66 g/t gold and 11.5 g/t silver over 1.98 m from 50.75 m downhole
· 6.66 g/t gold and 11.7 g/t silver over 6.97 m from 20.0 m downhole including;
· 8.32 g/t gold and 12.0 g/t silver over 5.52 m from 21.45 m downhole including;
· 19.80 g/t gold and 23.3 g/t silver over 2.0 m from 23.0 m downhole
· 5.13 g/t gold and 14.6 g/t silver over 4.42 m from 13.26 m downhole including;
· 11.5 g/t gold and 20.7 g/t silver over 1.58 m from 13.26 m downhole
Note: All numbers are rounded and widths represent downhole lengths. True thickness is estimated at 75-85% of downhole thickness.
The company also completed two deeper holes in 2020 to assess depth extensions in areas of widely spaced drilling. These holes each intersected a wide vein, but gold mineralization is low grade. Epithermal veins have natural variability in the distribution of mineralization, and these are the first two holes of a 10-12 hole program that the company plans to drill to systematically infill the loosely defined areas to better constrain the distribution of gold.
The deepest completed hole to date at SH-1 intersected 23.99 g/t gold over 5.48 metres in hole BM-01 and the company will continue expand to depth where the system remains open.
The Apollo and Sitka workings sit along a seven-kilometres long southwest- trending vein corridor that hosts multiple veins and runs sub-parallel to the Shumigan vein corridor (host to SH-1 and Aquila).
A northwest dipping sequence of basaltic andesite interbedded with volcaniclastic sandstones hosts the Apollo mineralization. An open stope that exploited three veins extends for over 300 metres along strike and about 425 metres in depth. Veins outlined to date strike northeast and dip both steeply northwest and southeast. The veins contain coarse comb-textured quartz with calcite, pyrite, galena, sphalerite and chalcopyrite.
The company drilled three holes beneath the Apollo mine (Figure 1, Apollo stopes area). The first hole intersected mine workings at the target depth, the second deviated to the east, away from the target and the third intersected two veins with the best intercept of 1.95m grading 5.10 g/t gold equivalent.
· 5.10 grams per ton (g/t) gold equivalent (4.77 g/t gold, 14.3 g/t silver, 0.1% lead and 0.2% zinc) over 1.95 metres (m) from 157.89 m downhole
· 1.06 g/t gold equivalent (0.30 g/t gold, 11.9 g/t silver, 0.7% lead and 0.8% zinc) over 24.99 m downhole from 5.79 m downhole
Note: All numbers are rounded, and widths represent downhole lengths; true thicknesses are unknown. Gold equivalent is calculated using the following formula: gold-equivalent = ((Au_g/t x 48.23) + (Ag_g/t x 0.6431) + (Pb_ppm x 0.0019) + (Zn_ppm x 0.0021)) / 48.23. Metal price assumptions are $1,500 per ounce gold,$20 per ounce silver, $0.85 per pound lead and $0.95 per pound zinc.
The Aquila target is a series of outcropping epithermal quartz veins located along the Shumigan vein trend. Heliostar targeted the area because historic work showed multiple areas of outcropping mineralization whilst limited, widely spaced drilling did not match surface results.
In the early 1980s, a UNC Teton Exploration Drilling Inc. operated program discovered the area and defined multiple veins over a 1,000 metre by 500 metres area within an interpreted zone of structural dilation. Trenching along the main vein zone returned a best result of 11.48 g/t gold and 53.47 g/t silver over 3.66m (The qualified person has not been able to independently verify the historical assay results presented above and Heliostar’s drilling is to establish the grades and widths of vein targets at Aquila).
Poor core recovery handicapped historic drill holes at nine locations throughout the Aquila target area. No significant other exploration occurred there since the early 1980s until Heliostar’s drill program in 2020.
The recent drill results have added a new interpretation of mineralization that significantly expands the potential for mineralization at Aquila. Mineralization is open at depth and along strike in both directions.
Heliostar commenced drilling at the approximate location of a historic hole that had poor core recovery in the target vein zone, with hole AQ20-01 and follow-up holes AQ20-02 to AQ20-05 testing the vein both along strike and at depth.
This drilling had significantly improved core recovery from the main Amethyst vein and
has defined a second vein orientation, the Ankle Creek vein, which is a very favorable development allowing considerable room for expansion along strike and at depth.
· 4.46 g/t gold over 3.6 m from 37.55 m downhole, and
· 2.24 g/t gold over 17.37 m from 46.63 m downhole including;· 5.56 g/t gold over 5.75 m from 50.25m downhole
Note: All numbers are rounded and widths represent downhole lengths. True thickness is estimated at 35-90% of downhole thickness.
The Centennial gold deposit is an area of widespread disseminated and stockwork gold mineralization with a broad north-northwest trend and extents of at least 1,200 metres in length and about 600 metres in width. The mineralization is coincident with propylitic and silicic-potassic (adularia) alteration that is hosted within basaltic andesites, andesitic volcaniclastic rocks, conglomerates, finely-laminated tuffaceous sediments, and minor white felsic lithic tuff.
Drilling at Centennial defined a historic, non 43-101 compliant resource of 4.8 million tonnes at an average grade of 1.43 g/t gold.
This mineral resource estimate was not prepared in accordance with National Instrument 43-101 nor in accordance with guidelines of the Canadian Institute of Mining and Metallurgy. Heliostar is not treating this resource estimate as current.
Previous workers interpreted the bulk of mineralization as subhorizontal but there is evidence in sea-cliff exposures at the southern extent of the prospect area for a high-angle structural control that may host higher grades. However, previous
work didn’t test this concept due to insufficient drill density and the predominance of vertical holes. Most of the identified gold lies within 50 metres of the surface, however, the historic drilling was largely shallow (<200 metres deep) and only six of the 59 holes penetrated deeper than 150 metres.
The Centennial deposit provides an example of potential bulk-tonnage-style gold mineralization at the Unga project.
The company owns 100% of three gold-silver epithermal projects in northern Sonora State, Mexico – La Lola, Cumaro, and Oso Negro. This region hosts many high-grade gold and silver deposits. Cumaro forms part of the El Picacho district, while the Oso Negro and La Lola projects are also prospective for epithermal gold-silver mineralization.
The La Lola property is a 63.6 square kilometres land package near Equinox Gold’s Mercedes mine, First Majestic Silver’s Santa Elena mine, SilverCrest’s Las Chispas deposit, Silver Tiger Metals’ El Tigre deposit and Grupo Mexico’s giant La Caridad mine.
The property includes the prospective La Barra vein, a 5-kilometres-long quartz- carbonate-fluorite vein with elevated values of gold, silver, and pathfinder elements. Despite being a prominent target, the vein had never been drilled. In outcrop the vein is up to 40 meters wide and has textures typical of shallow epithermal formation. Broad clay alteration, fluorite and low temperature textures suggest that the surface expression of the La Barra vein is the top of an epithermal system and that the metal-rich zone of the epithermal system may exist at depth.
Precious metals values in rocks hold low values as we expect, based on the shallow level expression of the geological model. However, values up to 0.44 g/t gold have been found within the vein and values of 56.6 g/t gold and 424 g/t silver have been found within the larger area and are interpreted to represent stronger pulses of mineralization which were able to propagate closer to the surface. Historic mining on the vein has focused on fluorite that occurs near surface within the vein zone and is a shallow level feature of other productive systems such as at the Los Gatos mine in Chihuahua.
The company began drilling at La Lola in 2021 and a total of 1,500m of core drilling is planned. Several other vein zones are present and have received little historical sampling or mapping and represent further exploration opportunities.
Cumaro is a five square kilometres claim lying within SilverCrest’s actively explored El Picacho district and hosts the extensions of the El Picacho, Dos Amigos, and Basaitegui Veins. In February, SilverCrest announced the completion of 42 holes with 21 holes intercepting an average of 4.1 meters estimated true vein width grading 8.14 g/t gold and 49.7 g/t silver 1. The best hole reported, PI-20-006, returned 7.25 meters of estimated true vein width grading 40.49 g/t gold and 260.4 g/t silver. These intercepts are about 1,800 meters along strike from Heliostar’s Cumaro claim.
The El Picacho Project is a neighboring project that is not owned by Heliostar Metals Limited. There is no guarantee Heliostar will return similar exploration results as at El Picacho.
The geology of the El Picacho - Cumaro district comprises two parts divided by a fault. In the western half, outcropping precious-metal bearing veins project directly from the El Picacho claim on to the Cumaro claim.
The eastern half hasbeen interpreted as downthrown compared to the western half. That potentially preserved the El Picacho mineralized level at shallow depth.
Surface alteration at Cumaro comprises corridors of clay, quartz, and calcite; assemblages that support the shallow level geological interpretation of the western block at Cumaro. The vein extensions on the Cumaro claim have received little exploration work and no known drilling. Work is currently underway to advance exploration at the vein extensions to drill ready status.
Oso Negro is a historic mining district with outcropping veins returning samples up to 2,680 g/t silver and 100.5 g/t gold from dump samples. Within the district, many veins are known and can be traced for hundreds of meters at surface, including the El Sahuaro, El Prospecto, Santa Rosa, Del Monte, Tere, and El Manchuri Veins.
Systematic exploration work is underway and will advance the known vein occurrences to a drill decision point.
Note 1: SilverCrest Metals Inc. news release dated February 24, 2021
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