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Gold Standard Ventures Corp
Symbol GSV
Shares Issued 246,231,646
Close 2017-09-25 C$ 2.03
Market Cap C$ 499,850,241
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Gold Standard's Dark Star bottle roll recoveries at 88%

2017-09-25 07:07 ET - News Release

Mr. Jonathan Awde reports

GOLD STANDARD VENTURES REPORTS BOTTLE ROLL RECOVERIES AVERAGING 88% FOR THE DARK STAR OXIDE GOLD DEPOSIT

Gold Standard Ventures Corp. has released positive metallurgical results from continuing work designed to determine the processing characteristics of the Dark Star oxide gold deposit, on its 100-per-cent-owned/controlled Railroad project in Nevada's Carlin trend. Bottle roll recoveries from minus-10-mesh-size material averaged 88 per cent for Dark Star oxide and transition materials. Results indicate this material is likely to support heap leach processing.

Bottle roll testing for cyanide solubility of Dark Star core samples was completed by Kappes Cassiday and Associates of Reno, Nev., under the direction of Gary Simmons, consulting metallurgical engineer. Bottle rolls were completed on drill core samples at both minus-10-mesh- and minus-200-mesh-size fractions. The results will be combined with column leach testing currently in progress to predict gold recoveries in a cyanide heap leach operation. At Dark Star, a total of 62 samples representative of the gold deposit were tested using bottle rolls at the two different size fractions. Oxide and transitional material thought to be suitable for heap leaching was subjected to testing to determine ranges of gold recovery. At Dark Star, gold recoveries for oxide and transitional in the coarse minus-10-mesh bottle rolls of material ranged from 60 to 98 per cent, with an average gold recovery of 88 per cent. In the finer minus-200-mesh bottle rolls gold recovery ranged from 75 to 98 per cent, with an average gold recovery of 91 per cent.

According to Mr. Simmons, "Data from metallurgical bottle roll testing to date at Dark Star point to high gold leach extraction from oxidized materials and suggest that simple heap leaching of crushed and/or run-of-mine material may be the preferred process option at Dark Star."

Jonathan Awde, chief executive officer and director of Gold Standard, commented: "This is an important further step in determining the economic potential of the high-grade near-surface Dark Star gold deposit. Not only are the initial recoveries very encouraging but also the amount of preparatory grinding and reagent consumption required appear to be very manageable. Our ongoing aim is to complete a preliminary economic assessment this year that confirms our belief that the Dark Star deposit can become a low-cost gold producer."

Key highlights

Oxide and transitional material at Dark Star is amenable to cyanide leaching, as confirmed by bottle roll testing summarized in the associated table.


Mineralized                      Number      Average   -10 mesh  -10 mesh     Average   -200 mesh   -200 mesh 
area/rock            Material of bottle    gold head       gold   average   gold head        gold     average
type                     type     rolls    grade -10   recovery      gold  grade -200    recovery        gold 
                                          mesh (g/t)      range  recovery  mesh (g/t)       range    recovery

Main Dark Star          oxide        11         0.67     70-98%       87%        0.69      82-95%         90%
Main Dark Star   transitional         3         1.43     68-87%       82%        1.44      75-91%         87%
North Dark Star         oxide        48         1.63     60-97%       88%        1.60      76-98%         92%
                    oxide and
All Dark Star    transitional        62         1.45     60-98%       88%        1.43      75-98%         91%

Cyanide-soluble gold assays confirm the consistently oxidized nature of gold mineralization within the Main Dark Star and North Dark Star gold zones, and suggest that the deposit will be amenable to heap leach processing.

Column leach tests for Dark Star are currently nearing completion and the company expects to receive final column leach results in late November. These results will be combined with the bottle roll results to predict gold recovery from a run-of-mine and/or crushed rock heap leach flowsheet and be incorporated into the preliminary economic assessment currently in progress on the project.

Reagent use in the bottle rolls for lime and cyanide consumption on oxide/transitional material is shown in the associated table. Lime consumption is low, while cyanide consumption is within a normal range for long leach time (72 to 144 hours) bottle tests of these material types.

                                                                                                      -200 mesh
Mineralized                          Number                  Average  -10 mesh   -10 mesh  -200 mesh    average
area/rock                Material of bottle      Average     organic      NaCN    Ca(OH)2       NaCN    Ca(OH)2 
type                         type     rolls sulphide (%)  carbon (%)   (kg/mt)    (kg/mt)    (kg/mt)    (kg/mt)

                                                           less than
Main Dark Star              oxide        11         0.07        0.01      0.26       1.18       2.22       0.61
                                                           less than
Main Dark Star       transitional         3         0.35        0.01      0.88       2.08       2.88       1.33
North Dark Star             oxide        48         0.11        0.11      0.22       0.89       1.52       0.65
                        oxide and
All Dark Star        transitional        62         0.12        0.11      0.27       1.00       1.72       0.68

Bottle roll testwork methodology

Core intervals from 68 composites from 13 Dark Star drill holes were selected based on gold grade (both AuFA and AuCN), oxidation state, sulphide content, lithology and alteration types. Bottle roll leach testing was conducted on portions of material from each sample. Sixty-two of the composites were either oxide or transitional in nature and were tested for cyanide leaching amenability. A 1,000-gram portion of crushed material (target 80 per cent passing 1.70 millimetres/10 mesh) was utilized for leach testwork. Additionally, a 1,000-gram portion of head material was milled in a laboratory rod mill to a target size of 80 per cent passing 0.075 millimetre (200 mesh). The milled slurry was then utilized for leach testing. For the coarse bottle rolls, the split material was placed into a 3.5-litre bottle and slurried with 1,500 millilitres of tap water. The mixed slurry was pH checked and adjusted to 10.5 to 11.0 as needed with hydrated lime. Sodium cyanide (NaCN) was added to the slurry, with a target of 1.0 gram per litre. Bottle was then placed on a set of laboratory rolls and checked at two, four, eight, 24, 48, 72, 96, 120 and 144 hours for pH, dissolved oxygen, NaCN, gold, silver and copper. Additional hydrated lime and sodium cyanide were added after each sample period to adjust the slurry to target levels. After completion, the slurry was then filtered, washed, dried and assayed. The finer 200-mesh bottle rolls were conducted using the same methods, although the samples were wet screened to ensure the finer-size fraction was achieved, and testing was stopped at 72 hours.

The metallurgical content and interpretations contained in this news release have been reviewed, verified and approved by Gary Simmons, BSc, metallurgical engineering, of G.L. Simmons Consulting LLC, MMSA-01013QP, a qualified person as defined by National Instrument 43-101, standards of disclosure for mineral projects.

Sampling methodology, chain of custody, quality control and quality assurance

All sampling was conducted under the supervision of the company's senior geologists and the company's metallurgical consultant Mr. Simmons. The chain of custody from the Gold Standard's Elko office to the sample preparation facility was continuously monitored. Sample pulps were delivered to ALS Minerals preparation facility in Elko, Nev., and shipped to ALS Minerals certified laboratory in Vancouver, B.C. Cyanide-soluble assays were determined by the Au-AA13s method. Quality control and assurance and data verification of the analytical results include a statistical analysis of the standards and blanks that must pass certain parameters for acceptance to ensure accurate and verifiable results.

Data obtained from this sampling were utilized to select core intervals for bottle roll and column leach testing at Kappes Cassiday and Associates in Reno, Nev. All metallurgical sampling was conducted under the supervision of the company's project geologists and the chain of custody from the company's Elko office to the KCA sample preparation and testing facility in Reno, Nev., was continuously monitored. Upon receipt, KCA weighed, photographed and assigned unique sample numbers for testing to material received. During testwork, all samples remained under the supervision of KCA and results were assayed and check assayed during testing procedures. Lab assays were conducted by KCA, with three analyses completed on each sample. Original head assays were performed at ALS (Reno, Nev.). During all stages of analysis appropriate standards and blanks were inserted by both Gold Standard geologists and laboratory staff. As part of the quality control and assurance all final results were verified and checked by both KCA and Mr. Simmons.

The scientific and technical content contained in this news release has been reviewed, verified and approved by Steven R. Koehler, Gold Standard's manager of projects, BSc, geology, and CPG-10216, a qualified person as defined by NI 43-101, Standards of Disclosure for Mineral Projects.

About Gold Standard Ventures Corp.

Gold Standard is an advanced-stage gold exploration company focused on district-scale discoveries on its Railroad-Pinion gold project, located within the prolific Carlin trend. The Dark Star deposit, 2.1 kilometres to the east of Pinion, now has a National Instrument 43-101-compliant resource estimate consisting of an indicated mineral resource of 15.38 million tonnes grading 0.54 gram per tonne gold, totalling 265,100 ounces of gold, and an inferred resource of 17.05 million tonnes grading 1.31 g/t Au, totalling 715,800 ounces of gold, using a cut-off grade of 0.20 g/t Au. The Pinion deposit has an NI 43-101-compliant resource estimate consisting of an indicated mineral resource of 31.61 million tonnes grading 0.62 g/t Au, totalling 630,300 ounces of gold, and an inferred resource of 61.08 million tonnes grading 0.55 g/t Au, totalling 1,081,300 ounces of gold, using a cut-off grade of 0.14 g/t Au (announced March 15, 2016).

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