Stockade Mountain Project, Oregon, US
On May 17, 2022, Austin Gold entered into a mineral lease agreement for exploration and mining rights and access to certain mineral claims on the Stockade Mountain Property situated in Malheur County, Oregon. Historical data generated within the project demonstrates the discovery potential for significant high-grade gold/silver mineralization occurring at shallow depth that may be amenable to underground mining.
Project Location and Access
Stockade Mountain is located approximately 50 miles (80 km) southeast of Burns, Oregon and 90 miles (145 km) southwest of Boise, Idaho. The high-grade gold/silver Grassy Mountain Gold project, which is currently undergoing permitting for an underground mine and adjacent milling operation, is located in Malheur County about 40 miles (64 km) northeast of Stockade Mountain.
Access to Stockade Mountain from Burns is by 29 miles (47 km) of paved State Highway 78, 43 miles (69 km) of good graded county gravel roads, and about 15.5 miles (25 km) of unimproved dirt roads, with a travel time of about 2.5 hours. Within the property are several 4-wheel drive vehicle accessible roads that enable access for exploration activities.
The property was explored by BHP, Phelps Dodge, and Placer Dome in the 1980s and 90s. The project is an exploration stage project. There are no known mineral resources or reserves on the project at this time. There has been insufficient exploration on the project to estimate a mineral resource.
Local Resources and Infrastructure
Stockade Mountain is located in a rural area used extensively for ranching and farming. The nearby community of Burns, Oregon is a commercial center for these businesses and can supply the necessary accommodation, food, fuels, supplies, and some of the contractors and workforce for exploration and development. Ontario, Oregon, located 70 miles (113 km) to the northeast is another significant commercial center in southeastern Oregon. The cities of Boise, Nampa, Caldwell and others in the “Treasure Valley” in adjacent Idaho can provide all necessary goods and services, including the international airport in Boise.
Property Claims and Lease
The Stockade Mountain property consists of a total of 261 unpatented lode mining claims that cover an area of over 6,790 acres (2748 ha) on land administered by the BLM.
The Stockade Mountain Lease is for a term of 50 years, with pre-production payments, work commitments, net smelter return royalties, and claim maintenance fees.
Stockade Mountain exhibits a classic large gold- and silver-bearing low-sulfidation “hot springs” hydrothermal system associated with rhyolite intrusion and doming that formed along a major NW-trending structural corridor.
Gold/silver and high-level mercury mineralization at Stockade is associated with widespread silicification and argillization in a near-surface paleo-hot springs environment. This hydrothermal alteration and mineralization formed in and around rhyolite domes that have intruded gently dipping felsic tuffs. Erosion into the hydrothermal system has been minimal, resulting in the local exposure of probable hydrothermal craters and vents that indicate the paleosurface at the time of hot springs activity. Gold and silver, along with associated elements arsenic, antimony, and mercury, are all strongly anomalous at the surface, however, historical drilling shows that gold and silver values, and their extent, increase significantly with depth below the paleosurface. This is a common characteristic of high-grade gold/silver deposits in similar geological environments, including the previously mentioned nearby Grassy Mountain deposit in Oregon, the Midas, Sleeper, Hollister, National, and Fire Creek mines in Nevada, and numerous analogous deposits elsewhere in the world. The hypothesized economic gold/silver veins at Stockade Mountain would have formed within the vertical zone of vigorous boiling of the hydrothermal fluids, and this is interpreted to have occurred approximately 600 to 1200 feet (183 to 366 m) below the surface.
Exploration programs conducted by BHP, Phelps Dodge and Placer Dome in the 1980s and 90s included shallow exploration holes that were drilled for bulk tonnage, open-pit potential, with no efforts to target deeper high-grade gold/silver vein deposits. Many of these short drill holes returned significant lengths of strongly anomalous gold mineralization, with the best intercept being:
- 79.2 m (260 ft) averaging 0.937 g/t gold from 45.7 – 125 m (150 – 410 ft), which includes:
- 24 m averaging 1.560 g/t gold from 58 to 82.3 m (190 – 270 ft).
Numerous other drill holes returned long intercepts of >0.2 g/t Au, and four drilled higher-grade intercepts of:
- 3 m (10 ft) averaging 1.1 g/t gold
- 1.5 m (5 ft) @1.14 g/t gold
- 4.6 m (15 ft) averaging 1.1 g/t gold
- 4.6 m (15 ft) that averaged 1.385 g/t gold.
The property had been dormant since the mid-1990s and was rediscovered by the vendors during an eastern Oregon reconnaissance exploration program. There has been a considerable amount of work done on the property in the past and the vendors have compiled a large amount of data for Stockade Mountain including:
- Assays for over 1,000 rock samples (includes 128 collected by the vendors and 230 collected by a previous exploration company);
- Approximately 1,000 soil samples (historical data);
- Information for 40 RC drill holes completed by Phelps Dodge, BHP-Utah, Placer Dome, and Carlin Gold;
- Recently completed ground and airborne geophysical surveys;
- A largely completed 43-101 Technical Report.
The Company plans to initiate a systematic exploration program to include drilling beneath the known property high-level gold/silver-bearing stockworks mineralization that will target high grade vein deposits formed deeper into the hydrothermal boiling zone along feeder conduits. Permitting with the United States Bureau of Land Management for the drilling program has been started.