The Robber Gulch Project is located in south-eastern Idaho, approximately 36 kilometers southeast of Twin Falls 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 April 2020 EMX has executed an option agreement for the Robber Gulch gold project in Idaho with Gold Lion Resources (NV) Inc., a subsidiary of Gold Lion Resources Inc. (CSE: GL; FWB: 2BC) (“Gold Lion”). The Agreements provide for share and cash payments to EMX, as well as work commitments during Gold Lion’s earn-in period for each given Project, and upon earn-in, a 3.5% net smelter return (“NSR”) royalty, annual advanced royalty payments, and milestone payments. See Company news release dated April 7, 2020 for more details.
The Robber Gulch Project comprises an area of strongly altered and mineralized Paleozoic silty carbonate and clastic units exposed within a window of post-mineral volcanic rocks. The Project lies 90 kilometers to the west, and within the same host sedimentary sequence as Liberty Gold Corp.’s Black Pine Carlin-style project in southern Idaho (see reference1). The primary targets at Robber Gulch are near surface, oxide Carlin-style gold mineralized zones associated with intense jasperoid, decalcified limestone, and local quartz veining and brecciation within sandstone and carbonate units.
EMX’s work has identified potential structural feeders and widespread zones of disseminated mineralization with anomalous gold and pathfinder elements. The Project has seen little modern exploration, with four shallow drill holes drilled in the mid-1980s, which were not followed up with further drilling or surface geochemistry. Results included hole AC-4 returning 18.3 meters @ 0.23 g/t gold (from 24.4m to 42.7m) and 24.4 meters @ 0.56 g/t gold (from 54.8m to 79.2m), including, 6.1 meters @ 1.25 g/t gold (from 64.0m to 70.1m) in oxide mineralization (true thicknesses unknown)2.
The Friday deposit’s lower grade, open pit constrained historic resource from 2013 (see reference3) was based upon US$1500/oz gold and 85% recovery applied to an inverse distance interpolated block model. A more recent historic resource focused on a higher grade, underground scenario at a 3.4 g/t gold cutoff that yielded measured and indicated resources of 462 Ktonnes @ 6.54 g/t Au (containing 97,200 oz Au) and inferred resources of 296 Ktonnes @ 4.91 g/t Au (containing 47,600 oz Au) which was based upon US$1300/oz gold and 94% recovery applied to an inverse distance interpolated block model4. EMX cannot verify the 2013 or 2017 historic resources, and a qualified person has not done sufficient work to classify the historic resources as current mineral resources. EMX is not treating the historic estimates as current mineral resources. It is EMX’s opinion that both the open pit and underground historic resources could be brought current with updated metal prices, cost estimates, and process recoveries, as well as confirmation drilling. An important step forward for Endomines to update the open pit resource was its acquisition of the open pit mining rights in late 20195.
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 Internal Report on Artesian City Project, Cassia County, Idaho. 1986. Exvenco Resources Inc.
3 NI 43-101 Technical Report, Idaho Gold Project. Prepared by Geosim for Premium Exploration Inc. 4/8/13.
4 See Endomines news release dated March 3, 2020 and Independent Expert’s Report from AMC Consultants to Endomines AB dated January 8, 2018.
5 See Endomines news release dated December 3, 2019.