Antioquia Gold Announces Preliminary Economic Assessment and Mineral Resource Update for Cisneros Gold Project

CALGARY, Alberta, Feb. 20, 2018 (GLOBE NEWSWIRE) -- Antioquia Gold Inc. ("Antioquia Gold" or the "Company") (TSX-V:AGD) (OTCQX:AGDXF) is pleased to announce that it has received an updated National Instrument 43-101 ("NI 43-101") compliant Preliminary Economic Assessment report (the "Report") for its Cisneros gold project in Antioquia Department, Colombia. The Report was prepared by Mr. Edgard Vilela, MAusIMM (CP), Independent Consultant with LINAMEC S.A.C, who is a "qualified person" as defined in NI 43-101.

The Report has been filed on SEDAR concurrently with this news release.  The Report will also be available on the Company website.

PEA Highlights

• Updated Mineral Resources for the Cisneros Properties, above cut off grade, for all mineralized structures consists of 728,603 tonnes of Measured + Indicated Mineral Resources with an average grade of 5.389 g/t Au and 536,211 tonnes of Inferred Mineral Resources with an average grade of 6.345 g/t Au.
• Mine production is projected to start in 2Q, 2018. The Guaico and Guayabito vein areas are planned to be mined by the cut and fill method and the Nus structures by Long Open Stoping method. The mining rate is projected to produce an average of 15,000 t/month of mineralized material. The process plant has been designed to operate 347 days per year overall and treat 500 tonnes of mineral daily.
• Gold design average ore head grade is estimated to be 6.43 g/t Au
• An overall recovery of 90% has been anticipated.
• Life-of-mine (LoM) of 5.0 years.
• LoM gold production of 150,900 ounces gold recovered.
• The project has a pre-tax net present value (NPV) of US$23.71M and post-tax NPV of US$16.75 M using a 5% discount rate.
• The project has a pre-tax internal rate of return (IRR) of 24.0% and post-tax IRR of 18.7% using a 5% discount rate.
• The total preproduction and sustaining capital cost estimated for the Cisneros project is US$75.5 M and includes expenses from 2014 to March 2018. The Capital cost consists of pre-production capital cost of US$61.5 M, sustaining capital cost of US$14.1 M and a contingency of 15% (US$7.8 M)
• Project payback is 2.6 years on a pre-tax basis.
• A mineralized stockpile of 19,402 tons will be maintained for the commissioning of the plant, as a result of the preparation of the stopes in the Guayabito and Guaico-Nus areas of the Cisneros Project.
• Mined ounces (in-situ) will increase from 28 koz in 2018 to 39 koz in 2019, and then decrease gradually for the remaining mine life.
• The Cisneros Project mine potential mill feed estimate was based on the updated mineral resources. A total of 516,351 tonnes at a grade of 5.44 g/t Au of measured and indicated resources and 268,412 tonnes at a grade of 6.812 g/t Au of inferred mineral resources were considered for the financial evaluation. The following assumptions were used as the criteria to estimate these economic mineral resources:
  --  The potential mill feed economic Mineral Resources are inclusive in reported mineral resources.
  --  Specific cut off was calculated for Guaico, Nus and Guayabito structures. A cut-off of 2.95 g/t Au for Guaico, 2.62 g/t Au for Guayabito and 1.66 g/t Au for Nus was estimated.
  --  Metal price, production, selling cost and recovery were considered as the major factors in the calculation of cut off grade.
  --  Gold price assumptions are no more than the average value for the last six months as indicated by the price fixes of the London Metal Exchange.
  --  General and administration cost and sustaining cost were not considered in the cut off grade estimation.
  --  Guayabito Sur structures and Papi veins were not included. These require more development that is economically not viable in comparison with current tonnage.
  --  Mineral resources within 30 m of surface are not considered. A pillar of 9 m width along each level will be left behind. Both of these reduce the initial resources.
  --  The potential economic mineral resource includes a historical mineral stockpile reported to contain 7,500 tonnes grading 5.1 g/t Au. The mineralized material was sourced from mine development up to September 30, 2017 on the Guaico and Nus mines.

Mineral Resource Estimate

The updated resource estimate incorporates results from 110 drill holes, including results of 14 new drill holes drilled in 2016-2017 and 1130 channels sampled during 2016 and 2017. The mineralized structures, updated with new data are: Nus, Guaico, Footwall-03, Footwall-05, Vega and La Manuela-01. Resources for Guayabito North and Papi, remain unaltered from the 2013 mineral resource estimate.

Updated mineral resources for the Cisneros Properties, above cut-off grade, for all mineralized structures consist of 760,731 tonnes of measured and indicated resources with an average grade of 5.233 g/t Au and 536,211 t of Inferred Mineral Resources with an average grade of 6.345 g/t Au.

Total Measured Resource Estimates for Cisneros Deposits

Total Indicated Resource Estimates for Cisneros Deposits

Total Measured + Indicated Resource Estimates for Cisneros Project

Total Inferred Resource Estimates for Cisneros Deposits

1. Mr. Edgard Vilela, is the Qualified Persons and Chartered Professional for the Mineral Resource estimate. The effective date of the estimate is September 24, 2017.
2. Mineral Resources are reported using a cut-off grade of 2.95 g/t Au for GCO, GCFW3, GCFW5 and MNL_1.
3. Mineral Resources are reported using a cut-off grade of 1.66 g/t Au for NUS and 1.50 for PAPI.
4. Mineral Resources are reported using a cut-off grade of 2.62 g/t Au for GYB-SUR and 2.50 for GYB.
5. Reported Mineral Resources contain no allowances for hanging wall or footwall contact boundary loss and dilution. No mining recovery has been applied.
6. Rounding as required by reporting guidelines may result in apparent summation differences between tonnes, grade and metal content.

Underground Mining

The base case scenario for the Project includes mining of measured, indicated, and inferred mineral resources with underground Cut and Fill ( C&F ) and Longhole Open Stoping mining methods.

Preliminary assumptions for Cut and Fill Mining method is that it is a selective mining process. The dilution for veins lower than 0.8 metres in width were not considered as part of the block modelling process for veins on Cisneros projects. Block model are diluted to 0.8 m and no additional dilutions were considered for the mine plan in these preliminary evaluations.

The mining recovery factor is depended on results of rock mechanics studies. For every 100 vertical metres it is suggested to leave a nine metre horizontal pillar which will be dependent on the vertical extent of each vein’s geometry. The following table shows the dilution and mining recovery factor for C&F mining based on specific calculations that were considered for dilution and mining recovery factors during mine plan scheduling.

Mining Recovery Factor for Cut and Fill mining

A mining recovery of 92% is assumed for longhole open stoping Mining. The mining recovery factor is depended on rock mechanics recommendations. Again it is suggested to leave a nine metre horizontal pillar for every 100 vertical metres.

Process Plant

The objective of the metallurgical process is to obtain gravimetric concentrates and flotation concentrates in a plant with a capacity of 500 tonnes per day (tpd). The plant will be composed of a single production line in two conventional processes namely gravity followed by flotation to obtain sulphide concentrates containing gold.

The process plant has been designed to operate 347 days per year and treat 500 tonnes of material daily. The average head grade is estimated to be 6.43 g/t Au and an overall recovery of 90% is anticipated. Mineable resources have been estimated at 784,763 tonnes with a life-of-mine ( LoM ) of five years. A stockpile of 19,402 tons, resulting from development of stopes in the Guayabito and Guaico-Nus areas will be maintained for the commissioning of the plant.

The general flow sheet of the plant process consists of four sections to produce gold concentrates. These include primary and secondary crushing, grinding and gravity, flotation and concentrate filtration.

Capital and Operating Costs

The total preproduction and sustaining capital cost estimated for the Cisneros project is US$ 75.5 M and includes expenses incurred from 2014 to March 2018. Preproduction capital cost is US$ 61.5 M and sustaining capital cost is US$14.1 M.  Capital costs include a contingency of 15% (US$ 7.8 M).

The capital cost profile for the Cisneros Project includes pre-production and sustaining capital. Sustaining capital includes expenses incurred during the expected production period of April 2018 to 2022. All capital costs were estimated for a 3,000 tonnes per month mill capacity.

Economic Analysis and Cash Flow Results

A pre-tax and post-tax cash flow model was developed for the Cisneros project. The financial evaluation presents results for Net Present Value (“NPV”), Internal Rate of Return (IRR) and payback period. All the evaluations include only CAPEX and Sustaining capex from 2017 to LoM and a contingency of 15%. Capital expenditures prior to 2017 of US$13.2 M are included as indicated in the audited financial statements of Antioquia for 31-Dec-2016.
The results show that the project has a pre-tax IRR of 24.0% and pre-tax NPV of $23.7M and post-tax IRR of 18.7% and post-tax NPV of $16.7 M.

Cisneros Gold Project economic model summary

Cash costs of production are estimated at US$697 /oz with all in costs including closure and capital costs estimated at US$1,146 /oz

Operating Cost Analysis

Sensitivity Analysis

The NPV is most sensitive to metallurgical recovery, gold price and gold grade and less sensitive to OPEX and CAPEX.

Cisneros Project Post-Tax @ 5% NPV Sensitivity Analysis

Subsequent Drilling after PEA Effective Date

During the preparation of the PEA an exploration campaign was carried out with diamond drilling from surface. A total of 2,912.00 meters were drilled in the areas of Guayabito, Nus and Guaico. 2,344.20 metres of drilling were included and reported in the PEA and 567.80 meters were not reported in the PEA as results were obtained after the effective date of the PEA.  AGD’s management believes the results of these drillholes will not materially impact the PEA results.

Drill Hole Highlights

Drill Hole Specifications

Sample Preparation, Assays, and Quality Assurance/Quality Control (“QA/QC”)

Core is collected, logged (geological & geotechnical), cut and sampled at Antioquia’s drilling warehouse in the project area. All quality control (“QC”) samples are introduced before shipment to SGS sample preparation facilities in Medellin, Colombia. The prepared samples are analyzed by SGS analytical facilities in Medellín, Colombia. Gold is assayed by fire- assay with Atomic Absorption finish using a 30 gram aliquot sample. Multi- element analysis is achieved by Four Acid Digestion and an Induced Coupled Plasma- Emission Spectroscopy finish.

The Company's QA/QC program includes the regular insertion of blanks, multiple certified assay standards, twin samples and duplicate samples into the sample shipments. These QC samples are inserted in every assay batch with each batch comprising 12% of such samples. Monitoring of these QC samples is a critical part of Antioquia’s QA/QC protocols that involve the re-analysis of a minimum of 10 samples bounding any failed control sample. A third party check laboratory receives 5% of all samples to verify the original assays.

Subsequent Tests

Following the Effective Date of the PEA, the Company performed mineralized material sorting system tests to determine if the grade of the material can be optimized for processing purposes. As of the date of this news release, the Company had not received the official results of these tests.

Qualified Persons

Mr. Edgard Vilela, MAusIMM (CP), is a Qualified Person as defined in NI 43-101and has reviewed and approved the scientific and technical disclosure in this release and has verified the data disclosed.

This press release has been prepared under the supervision of Dr. Roger Moss, Ph.D., P.Geo a Qualified Person as defined by NI 43-101. 

On behalf of the Antioquia Gold Board of Directors

Mr. Gonzalo de Losada, President and Chief Executive Officer
Antioquia Gold Inc.

For further information on Antioquia Gold Inc., visit our website at www.antioquiagoldinc.com

Phone: 1-800-348-9657.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this press release.

Reader Advisory  Forward-Looking Statements:

This press release contains "forward-looking information" within the meaning of Canadian securities legislation. This information and these statements, referred to herein as “forward-looking statements”, are made as of the date of this press release and the Corporation does not intend, and does not assume any obligation, to update these forward-looking statements, except as required by law.

Forward-looking statements relate to future events or future performance and reflect current expectations or beliefs regarding future events and include, but are not limited to, statements with respect to: capital expenditures, operating costs, and the anticipated project schedule. Any statements that express or involve discussions with respect to predictions, expectations, beliefs, plans, projections, objectives, assumptions or future events or performance (often, but not always, using words or phrases such as “expects”, “anticipates”, “plans”, “projects”, “estimates”, “assumes”, “intends”, “strategy”, “goals”, “objectives”, “schedule” or variations thereof or stating that certain actions, events or results “may”, “could”, “would”, “might” or “will” be taken, occur or be achieved, or the negative of any of these terms and similar expressions) are not statements of historical fact and may be forward-looking statements.

Forward-looking statements are made based upon certain assumptions by the Corporation and other important factors that, if untrue, could cause the actual results, performances or achievements of the Corporation to be materially different from future results, performances or achievements expressed or implied by such statements. Such statements and information are based on numerous assumptions regarding present and future business prospects and strategies and the environment in which the Corporation will operate in the future, including the accuracy of any resource estimations and economic assessments, the availability of financing on resonable terms or at all, the price of gold, anticipated costs and the Corporation’s ability to achieve its goals, anticipated financial performance, regulatory developments, development plans, exploration, development and mining activities and commitments. Although management considers its assumptions on such matters to be reasonable based on information currently available to it, they may prove to be incorrect. Additional risks are described in Antioquia's most recently filed Annual Information Form, annual and interim MD&A and other disclosure documents available under the Corporation’s profile at: www.sedar.com.

By their very nature, forward-looking statements involve inherent risks and uncertainties, both general and specific, and risks exist that estimates, forecasts, projections and other forward-looking statements will not be achieved or that assumptions do not reflect future experience. We caution readers not to place undue reliance on these forward-looking statements as a number of important risk factors could cause the actual outcomes to differ materially from the beliefs, plans, objectives, expectations, anticipations, estimates, assumptions and intentions expressed in such forward-looking statements.

Readers should also be cautioned that the Corporation’s decision to move forward with the construction and production of the Cisnero Mine is not based on the results of any pre-feasibility study or feasibility study of mineral resources demonstrating economic or technical viability. Since 2013, the Corporation has undertaken exploration and development activities; and after taking into consideration various factors, including but not limited to: the exploration and development results to date, technical information developed internally, the availability of funding, the low starting costs as estimated internally by the Corporation’s management, the Corporation is of the view that the commissioning of a pre-feasibility study, the establishment of mineral reserves, or the commissioning of a feasibility study at this stage is not necessary, and that the most responsible utilization of the Corporation’s resources is to proceed with the development and construction of the mine. Readers are cautioned that due to the lack of a pre-feasibility study or feasibility study, there is increased uncertainty and higher risk of economic and technical failure associated with the Corporation’s decision. In particular, there is additional risk that mineral grades will be lower than expected, the risk that construction or ongoing mining operations will be more difficult or more expensive than management expected. Production and economic variables may vary considerably, due to the absence of a detailed economic and technical analysis in accordance with NI 43-101. Project failure may materially adversely impact the Corporation’s future profitability, its ability to repay existing loans, and its overall ability to continue as a going concern.

Cautionary Note For US Investors Concerning Estimates of Measured, Indicated and Inferred Resources

This press release uses the terms “measured”, “Indicated” and “Inferred” resources.  These estimates have been prepared in accordance with the requirements of Canadian securities laws, which differ from the requirements of United States’ securities laws. The terms “mineral resource”, “measured mineral resource”, “indicated mineral resource” and “inferred mineral resource” are defined in NI 43-101 and recognized by Canadian securities laws but are not defined terms under SEC Guide 7 or recognized under U.S. securities laws. U.S. investors are cautioned not to assume that any part or all of mineral deposits in these categories will ever be upgraded to mineral reserves. “Inferred mineral resources” have a great amount of uncertainty as to their existence, and great uncertainty as to their economic and legal feasibility. It cannot be assumed that all or any part of an “inferred mineral resource” will ever by upgraded to a higher category. Under Canadian securities laws, estimates of “inferred mineral resources” may not form the basis of feasibility or pre-feasibility studies, except in rare cases. U.S. investors are cautioned not to assume that all or any part of an inferred mineral resource exists or is economically or legally mineable. Accordingly, these mineral reserve and mineral resource estimates and related information may not be comparable to similar information made public by U.S. companies subject to the reporting and disclosure requirements under the United States federal laws and the rules and regulations thereunder, including SEC Guide 7..