Mr. Rodrigo Barbosa reports
AURA REPORTS UPDATED MINERAL RESERVES AND MINERAL RESOURCES
Aura Minerals Inc. has released updated mineral reserves and mineral resources (MRMR) estimates for its three operating mines: the San Andres mine, the Ernesto/Pau-a-Pique mine (EPP) and the Aranzazu mine, as well as its development projects, including the Matupa project and the Almas project, as reported in the annual information form (AIF) for the year ended Dec. 31, 2022.
Readers are encouraged to read the 2022 AIF and technical reports (as defined herein), which have been filed on SEDAR.
Rodrigo Barbosa, president and chief executive officer of Aura, commented: "In 2022, we laid the groundwork to meet our robust growth objectives in the coming years to reach over 450,000 GEO annualized by 2025 through stable production, growth in mineral resources and mineral reserves, and adding to our pipeline through M&A [mergers and acquisitions]. Given that we only started ramping up our investment in exploration in recent years, our strategy in 2022 focused on increasing mineral resources across our projects; we had a conversion rate of over 100 per cent on inferred mineral resources and added 865 kGEO in measured and indicated (M&I) mineral resources, and 592 kGEO in inferred resources (both before depletion/conversion). We also saw an important increase in mineral reserves by adding 742 kGEO of proven and probable (P&P) mineral reserves in 2022 (before depletion), comfortably exceeding the 2022 depletion. We are focused on increasing our mineral reserves and on making new discoveries."
Mr. Barbosa continued: "Beyond our reported numbers, we expect imminent increases to our mineral resources base through a number of high-priority opportunities. Firstly, at our Borborema project, acquired in late 2022, which is in the feasibility study stage focused on converting the historic JORC [joint ore reserves committee] mineral resources to NI 43-101 compliant Mineral Resources. Secondly at our EPP Mines, we see significant expansion opportunities where drilling at depth and connection between pits continues to show promise. We also acquired Japones Oeste, an important area located along strike of the existing pits, where drilling continues. Thirdly we will focus regionally, at the Matupa project we've only begun to understand the geological potential at the Serrinhas target 20 km from the X1 deposit, where we have mineral reserves, and at Serra de Estrela, we are enthusiastic to start our first exploration program soon within the world-class Carajas region to enhance our exposure to copper. We look forward to providing additional updates on our various exploration initiatives and highlight our measured and diverse approach to growth in high-quality ounces."
Two thousand twenty-two highlights
The company completed another robust exploration program totalling 123,895 metres of drilling across its material properties. In 2022, Aura invested approximately $22-million (U.S.) in exploration with the initial goal of increasing total mineral resources (M&I plus inferred), which is expected to be followed by an increase in P&P reserves in the following stage.
The company's strategy to increase mineral resources was successfully achieved in 2022, with a total of 865 ounces of M&I mineral resources added (before depletion/conversion) and 592 ounces of inferred mineral resources. This addition does not consider ounces for the Borborema project, currently under feasibility study stage, and potential mineral resources from certain near-term targets, such as Serrinhas (Matupa) and Japones Oeste (EPP), which are being further explored in 2023.
Inferred mineral resource additions totalled 592 kGEO (before depletion/conversion). The small net reduction in inferred mineral resources between 2021 and 2022 was primarily due to the successful conversion of over 100 per cent of inferred mineral resources to M&I mineral resources at the three operating mines.
Measured and indicated mineral resource additions totalled 865 kGEO (before depletion/conversion). More than 100 per cent of depleted metals were replaced at each of the sites by converting both inferred mineral resources and previously undisclosed mineral resources into M&I mineral resources.
Proven and probable mineral reserves additions totalled 742 kGEO (before depletion). At the three operating mines, an increase of 433 kGEO (before depletion) comfortably exceeded the company's 2022 depletion on a consolidated basis. Additionally, 309 kGEO were added at Matupa following the previously reported feasibility study in November, 2022.
In September, 2022, Aura acquired Big River Gold Ltd., located in the municipality of Currais Novos, Rio Grande do Norte state, in the northeast of Brazil. The Borborema project is currently in the feasibility study stage. The Borborema project has a JORC-compliant measured and indicated mineral resources of 1.8 Moz Au at 1.14 g/t (grams per tonne) Au and an additional inferred mineral resource of 0.57 Moz Au at one g/t Au. This estimate is not prepared under National Instrument (NI) 43-101 -- Standards of Disclosure for Mineral Projects and is based on the @Definitive Feasibility Study Report, Borborema Gold Project. Cascar and Big River, November 19, 2019." A qualified person (as defined in NI 43-101) has not done sufficient work to classify this historic estimate as a current mineral resource under CIM guidelines. Accordingly, this historical estimate should not be relied upon as additional work is required to upgrade and verify the historical estimate as a current mineral resource.
Aranzazu mine, Mexico
At the Aranzazu mine, the primary focus for infill and exploratory drilling has been at the Glory Hole (GH) and Cabrestante zones. At the time of the update of the MRMR of Aranzazu, several assay results were still pending from the infill and exploration drilling and were not included in the mineral resources update in 2022.
Changes in mineral resources include the conversion of 550,000 tonnes and 770,000 tonnes from the inferred to M&I Mineral Resources in the GHFW4 and GHHW5 zones, respectively. Approximately 1.4 million tonnes were added to GHHW zone, and 390,000 tonnes were added to GHFW zone in the inferred resource category. Exploration and infill drilling in Cabrestante zone contributed an additional 567,000 tonnes to inferred mineral resources and converted approximately 290,000 tonnes to M&I mineral resources with grades increasing 10 per cent for copper, 52 per cent for silver and 30 per cent for gold.
Changes in P&P mineral reserves include an overall increase of 3.2 million tonnes in P&P (49.7 per cent) with an increase of gold ounces (24.7 per cent) and silver ounces (40 per cent), and an increase of 9 per cent on the net smelter return (NSR) due to a slight increase in the copper price. This increase compensates for the entire 2022 depleted tonnes. There was an important change (35.5%) in the volume of the main body of Aranzazu ("GHFW zone"), which represents 63 per cent of the current mineral reserve after infill drilling and converting mineral resources to mineral reserves by the end of 2022. GHHW zone had expanded after infill drilling and accounted for about 25 per cent of the 2022 current mineral reserves.
Ernesto and Pau-a-Pique, Brazil
During 2022, the infill and exploratory drilling campaign was focused at the Lavrinha mine, Nosde mine extensions at depth and Ernesto mine. Near mine exploration drilling in Lavrinha and Nosde increased the mineral footprint and generated an integrated model which connects these mines from southeast to northwest at depth. The integrated model was established and used to report inferred mineral resources for Lavrinha mine in 2022, resulting in an increase in inferred mineral resources.
Changes in mineral resources include over 100 per cent of the depleted M&I mineral resources being replaced, 147,000 ounces added to M&I mineral resources supported by the drilling at the Nosde mine (adding 129,000 ounces) and over 100 per cent of the converted inferred mineral resources replaced for 2.9 million tons containing 144,000 ounces.
Changes in mineral reserves include the replacement of 49 per cent of the of depleted P&P. However, the increase in total mineral resources, along with pit optimization studies and new drilling programmed for 2023, present great prospects for P&P mineral reserves increase in the short-term.
In late 2022, Aura acquired a new mineral right, Japones Oeste, along strike of the Japones pit, an area that had historical artisanal mining, to better understand the continuity of the mineralization toward the west of the Japones pit.
San Andres mine, Honduras
As of Dec. 31, 2022, mineral resources estimated by Aura totalled 71.86 Mt (million tonnes) of M&I mineral resources at an average grade of approximately 0.49 g/t gold grade and inferred mineral resources of 5.87 Mt at an average grade of 0.73 g/t gold, and a 0.2-gram-per-tonne Au cut-off for oxide and a 0.27 g/t cut-off for mixed material. The mineral resources pit shell optimization did not consider any sulphide material. Note that the mineral resources are inclusive of mineral reserves. Mineral resources that are not mineral reserves do not have demonstrated economic viability.
The new drilling at Esperanza areas and a decrease in cut-off grade supported the increase of M&I mineral resources replacing over 100 per cent of depleted and converted ounces. The M&I mineral resources and inferred mineral resources was limited by oxide and mixed material.
Almas project, Brazil
On March 10, 2021, the company filed the Almas technical report (as defined herein) and expects to commence production in the second quarter of 2023. The Almas project has an estimated mineral reserve of 21.8 Mt at an average grade of 0.92 g/t Au. The reserve classification reflects the level of accuracy of the feasibility study.
Matupa project, Brazil
In November, 2022, an updated feasibility study was completed with changes to the resource model and classification resulting in an updated mineral resources and an addition of P&P mineral reserves for the project. The designed open-pit's P&P mineral reserves of gold are estimated to be about 8.5 Mt, with an average grade of 1.13 g/t Au, totalling around 309,000 ounces of gold metal contained.
The Matupa project mineral resources estimate is currently limited to the X1 deposit. Aura conceptually believes the exploration upside in the project area is significant and that further exploration work may expand the mineral resources at the project. In April, 2022, drilling at the nearby Serrinhas target resulted in several wide and high-grade intercepts including, 80 metres at 3.89 g/t Au and 59 metres at 3.14 g/t Au. Follow up drilling is continuing.
The complete 2022 mineral resources and mineral reserves estimates for all tonnage, metal grades, and metal content are shown below in the associated tables.
Quality assurance and quality control
Aura incorporates a rigorous quality assurance and quality control (QA/QC) program for all of its three mines and exploration projects which conforms to industry best practices, as outlined by NI 43-101.
For a complete description of Aura's sample preparation, analytical methods and QA/QC procedures, please refer to 2022 AIF and the applicable technical report, a copy of which is available on the company's SEDAR profile.
The scientific and technical information contained in this press release has been reviewed and approved by Farshid Ghazanfari, PGeo, geology and mineral resources manager, and Tiaozito V. Cardoso, FAusIMM, technical services director, each of whom is an employee of Aura and a qualified person within the meaning of NI 43-101.
All information of scientific and technical nature has been derived from the technical reports and any information arising since the date of the technical reports has been prepared under the supervision of Farshid Ghazanfari, PGeo, and Tiaozito V. Cardoso, FAusIMM. Readers are encouraged to read the following technical reports for the following mineral properties of the company:
San Andres: The technical report dated July 2, 2014, with an effective date of Dec. 31, 2013, and entitled "Mineral Resource and Mineral Reserve Estimates on the San Andres Mine in the Municipality of La Union, in the Department of Copan, Honduras," prepared for Aura Minerals by Bruce Butcher, PEng, former vice-president of technical services, Ben Bartlett, FAusIMM, former manager mineral resources, and Persio Rosario, PEng, former principal metallurgist;
- Aranzazu: The technical report with an effective date of Jan. 31, 2018, and entitled "Feasibility Study of the Re-Opening of the Aranzazu Mine, Zacatecas, Mexico," prepared for Aura Minerals by F. Ghazanfari, PGeo (Farshid Ghazanfari Consulting), A. Wheeler, CEng (independent mining consultant), C. Connors, RM-SME (Aura Minerals), B. Dowdell, CEng (Dowdell Mining Ltd.), P. Cicchini, PE (Call & Nicholas Inc.), G. Holmes, PEng (Jacobs Engineering), B. Byler, PE (Wood Environment and Infrastructure Solutions), C. Scott, PEng (SRK Canada), D. Lister, PEng (Altura Environmental Consulting), F. Cornejo, PEng (Aura Minerals Inc.);
- EPP: The technical report dated Jan. 13, 2017, with an effective date of July 31, 2016, and entitled "Feasibility Study and Technical Report on the EPP Project, Mato Grosso, Brazil," prepared for Aura Minerals by a group of third party consultants including P&E Mining Consultants Inc., MCB Brazil and Knight Piesold Ltd.;
- Almas: The technical report dated March 10, 2021, authored by F. Ghazanfari, PGeo (Aura Minerals), B.T. Hennessey (Micon International Canada), L. Pignatari, PEng (EDEM, Consultants, Brazil), T.R. Raponi, PEng (Ausenco, Canada), I. Dymov, PEng, (Independent Consultant Canada), P.C. Rodriguez, FAIG, (GE21 Consultants, Brazil) and A. Wheeler, CEng (Independent Mining Consultant, U.K.), and titled "Updated Feasibility Study Technical Report (NI 43-101) for the Almas Gold Project, Almas Municipality, Tocantins, Brazil";
- Matupa: The technical report "Feasibility Study Technical Report (NI 43-101) for the Matupa Gold Project, Matupa Municipality, Mato Grosso, Brazil," dated Nov. 18, 2022, with an effective date of Aug. 31, 2022, by F. Ghazanfari. PGeo (Aura Minerals), L. Pignatari, PEng (EDEM Consultants, Brazil), and H. Delboni PEng (HDA-Independent Mining Consultant, Brazil).
About Aura Minerals Inc.
Aura is focused on mining in complete terms -- thinking holistically about how its business impacts and benefits every one of the company's stakeholders: the company, its shareholders, its employees and the countries and communities the company serves. The company calls this "360-degree mining".
Aura is a mid-tier gold and copper production company focused on the development and operation of gold and base metal projects in the Americas. The company's producing assets include the San Andres gold mine in Honduras, the EPP gold mine in Brazil and the Aranzazu copper-gold-silver mine in Mexico. In addition, the company has the Tolda Fria gold project in Colombia and five projects in Brazil, of which, four are gold projects: Almas, which is under final phase of construction; Borborema and Matupa, which are in development; and Sao Francisco, which is on care and maintenance. The company also owns the Serra da Estrela copper project in Brazil, Carajas region, under exploration stage.
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