Robber Gulch, Idaho
The Robber Gulch Project is located 30 kilometers south of Burley, Idaho and consists of 117 unpatented lode mining claims covering approximately 9.3 square kilometers and contains Carlin-style gold mineralization similar to the past-producing Black Pine mine (434,800 ounces of oxide gold produced in the 1990s) 90 kilometers to the east1. In January 2022 EMX has executed, through its wholly-owned subsidiary Bronco Creek Exploration Inc., an exploration and option agreement (the “Agreement”) for the sale of the Robber Gulch gold project (“Project”) in Idaho to Ridgeline Exploration Corporation, a wholly-owned subsidiary of Ridgeline Minerals Corp. (TSX-V: RDG) (“Ridgeline”). The Agreement provides EMX with cash payments, share payments, and work commitments during Ridgeline’s earn-in period, and upon earn-in a retained 3.25% net smelter return (“NSR”) royalty interest, annual advance royalty payments, and certain milestone payments.. See Company news release dated January 26, 2022 for more details.
Robber Gulch is a Carlin-style gold property acquired by EMX in 2019 and then optioned to a third party in 2020 that completed work programs consisting of geological mapping, soil and rock chip geochemical sampling, trenching, and a reconnaissance drill program. This previous work confirmed several key gold zones that were delineated by coincident geochemical anomalies and prospective geology. The drill testing was limited in scope and in EMX’s judgement did not adequately test the target zones. The Project reverted back to 100% EMX control in Q3, 2021.
Previous work on the Project defined two main corridors of gold mineralization along the crest of a gently sloping ridge where prospective Paleozoic host rocks outcrop. Much of the remainder of the property is covered by shallow soil. A 2020 geochemical sampling program (conducted by previous partner Gold Lion Resources) identified robust 1,000 by 550 meter and 850 by 600 meter gold-in-soil anomalies2. Numerous lower level gold-in-soil anomalies are scattered across the property within an overlying sequence of less prospective host rocks.
Trenching across portions of the soil anomalies further defined priority oxide gold targets, including a trench interval of 189 meters averaging 0.43 g/t gold, with a higher grade sub-interval of 0.88 g/t gold over 45 meters. Historical drilling intercepted 57.9 meters (from 21.3 to 79.2 m) averaging 0.34 g/t gold, including 12.2 meters averaging 0.90 g/t gold (hole bottomed in 0.32 g/t gold)3. The last hole of Gold Lion’s 2021 program terminated prematurely in bedrock at 6.1 meters depth, and averaged 1.46 g/t gold across the drilled interval. True widths from the trenching and drilling are unknown.
EMX regards Robber Gulch as a highly prospective gold property within an emerging Carlin-style gold region in southern Idaho. The Company looks forward to the Ridgeline team advancing the Project with the knowledge gained from successfully exploring Carlin-style gold systems in Nevada.
Comments on Sampling, Assaying and Adjacent Properties. EMX has not performed sufficient work to verify the Project’s historical drill results, but considers this information as reliable and relevant based upon the Company’s independent field work and reviews of data from multiple sources.
The geochemical and trench results in this news release from previous partner Gold Lion Resources (CSE: GL) were sampled and assayed according to industry standard procedures, and reported according to NI 43-101 requirements. EMX believes that these results are reliable and relevant. All trench samples were logged and sampled by Gold Lion personnel. Certified reference material standards, blanks and pulp duplicates were inserted at a ratio of approximately two in every 10 trench samples. Rock samples were collected as continuous 2 to 3-metre-long chip samples along the entire length of the trenches. An effort was made to collect an even volume of bedrock along each interval in order to minimize bias in the chip sampling.
All rock samples were sealed in poly bags and were transported to MS Analytical’s laboratory in Langley, B.C., by Gold Lion personnel for preparation and analysis. Sample preparation was completed by crushing the entire sample to 70% passing -2mm, riffle splitting off 1 kilogram and pulverizing the split to better than 85% passing 75 microns. Using a 30 gram sub-sample, the gold values are determined by the fire assay method, with atomic absorption finish (code FAS-111), which reports results in parts per million (ppm) (equivalent to grams per tonne (g/t)). Using a 0.5 grab sub-sample, the remaining analytes were determined by multi-element ICP-AES with an aqua regia digest (code ICP-130). Representative samples from RG-TR-20-03 were re-analyzed by Cyanide Leach (code AU-CN00) with a AAS finish. A range of samples from low (0.149g/t) to high grade gold (1.502g/t Au; determined by FAS-111) were selected to represent a range of mineralized samples from the trenching program for reanalysis by Cyanide Leach. All analytical results are verified with the application of industry standard Quality Control and Quality Assurance (QA-QC) procedures.
The adjacent and nearby historic resources, deposits and mines referenced provide geologic context for the Projects, but this is not necessarily indicative that the Projects host similar tonnages or grades of mineralization. Based upon EMX’s independent field work, including geologic mapping and surface sampling, the historic resources and exploration results referenced are considered to be reliable and relevant.
1 Black Pine Mine 43-101 Technical Report on the Black Pine Gold Project, Cassia County, Idaho. Prepared by MDA for Liberty Gold Corp. 9/7/2018. Historic production: pg. 27
2 See Gold Lion Resources news releases dated June 16, and August 11, 2020.
3 Exvenco Resources Inc., 1986, Internal Report on Artesian City Project, Cassia County, Idaho.