Goldstrike is a Carlin-style, sediment-hosted gold property located in Washington County, southwest Utah (50 km northwest of St. George), with a stratigraphic and structural setting and gold mineralization similar to other sediment-hosted gold systems. Goldstrike is host to a past-producing mine with an extensive exploration database, a large number of shallow drill holes with unmined oxide gold intercepts, and numerous untested gold targets.
Goldstrike was an oxide, heap leach mine from 1988 to 1994. It produced ~209,000 ounces of gold and ~197,000 ounces silver from 8 million tonnes of ore at an average grade of 1.2 g/t gold from 12 shallow pits and closed due to low gold prices and lack of space on the leach pads.
Owner and operator
In August 2014, Liberty Gold purchased Cadillac Mining for 100% of the Goldstrike Property. The property consists of 903 unpatented federal lode claims administered by the U.S. Bureau of Land Management (BLM), 43 patented claims and two Utah State Leases for total area of 76.8 square km.
Since acquisition, Liberty Gold has compiled a digital database of drill holes (+1,500), blast hole samples (+100,000) and historic rock and soil samples, and has constructed a 3D model of geology and mineralization. The 2014 and 2015 fieldwork included collection of an additional 1,384 soil samples and 294 rock samples, staking of additional claims, detailed mapping and a successful ‘proof of concept’ reverse circulation drill program comprising 18 holes.
The 2016 infill and step-out drilling program was completed with the objective of targeting unmined and/or undrilled areas between and around the historic pits. The program also drill tested down-dip to the north of, and laterally beyond the 7 km long ‘Historic Mine Trend’ into areas where gold has been confirmed but not systematically drilled off. The drill program consisted of both reverse circulation (163 holes) and core drilling (10 holes). The ten core holes were used to provide sample material for metallurgical studies (including column testing) and provide samples for density measurements, which are needed for accurate resource estimation.
Final metallurgical results were released in April 2017, with a weighted average of 85.9% gold recovery from column leach tests. In addition to great recoveries that support a simple heap leach mining scenario, gold extraction has proven relatively insensitive to particle size. This supports a run of mine heap leach process. More information can be found in the following news release: April 3, 2017.
An independent maiden resource estimate for Goldstrike was announced in February 2018. The classified mineral resource estimate is quoted at a cut-off grade of 0.25 grams per tonne gold and consists of and an indicated resource of 865,000 ounces of gold at an average grade of 0.54 grams per tonne gold (49,553,000 tonnes) and an inferred resource of 274,000 ounces of gold at an averge grade of 0.52 grams per tonne gold (16,443,000). More information can be found in the following news release: February 8, 2018.
A link to the 43-101 Independent Technical Report and Resource Estimate for the Goldstrike Project, Washington, County, Utah, USA can be found at the top of this page.
Strong geology in established area
At Goldstrike, tertiary volcanic and sedimentary rocks rest unconformably on a basement of deformed middle and late Paleozoic carbonate and siliciclastic rocks. The sequence is cut by steep, arcuate oblique-slip faults that form a sequence of horsts and grabens. Mineralization is focused at the intersections of the unconformity with these faults.
Gold mineralization on surface and in shallow drill holes has been discovered over the entire property, wherever the basal unconformity of the Tertiary sequence is exposed, and particularly where it is cut by faults. Grades of up to 13 ounces per ton of gold have been encountered in past drilling. Significant intervals of moderate grade remain unmined, including:
- 2.05 g/t Au over 30.8 metres
- 1.25 g/t Au over 82.3 metres
- 2.21 g/t Au over 25.9 metres
In the Paleozoic section, mineralization is related to faults, and is often open to depth.
Past producing mine
Gold mineralization was discovered in the district in the late 1890’s with early mining (1900 – 1920) focused on gold-bearing, limonitic calcite veins and “quartz ledges" (jasperoids) that outcropped in and around the present mine workings. Modern exploration began in the 1980’s with the identification of Carlin-style gold mineralization and deposit models. Surface and near-surface deposits were defined and total production was on the order of 209,000 ounces of gold and 198,000 ounces of silver. Tenneco mined oxidized, disseminated, sediment-hosted gold ore with an average grade of approximately 1.2 gram/tonne (0.035 ounce/ton) from 12 pits along a northeast-striking trend that covers a distance of approximately 6.5 kilometers (4 miles). The property was sold to USMX in 1993 and the mine was closed in 1996 and fully reclaimed.
Further information on Goldstrike is available in the technical report entitled “Independent Technical Report and Resource Estimate for the Goldstrike Project, Washington County, Utah USA” effective February 8, 2018 and dated March 21, 2018, prepared by David Rowe, C.P.G with SRK Consulting (Canada) Inc.; James N. Gray, P. Geo. of Advantage Geoservices Ltd.; and Gary Simmons, MMSA, of GL Simmons Consulting LLC found at the top of this page or under Liberty Gold's issuer profile in SEDAR (www.sedar.com).
Moira Smith, Ph.D., P.Geo., VP Exploration and Geoscience, Liberty Gold, is the Company's designated Qualified Person within the meaning of NI 43-101 and has reviewed and validated that the information contained herein is accurate.