Mr. Rodrigo Barbosa reports
AURA PROVIDES EXPLORATION UPDATE AND PLANS FOR 2023
Aura Minerals Inc. has provided an update on exploration activities to date and advancement plans across its portfolio in 2023. Readers are encouraged to read the company's most recent annual information form dated March 30, 2023 (the 2022 AIF), which is available on SEDAR and the company's website, which includes current mineral resources and mineral reserves (MRMR).
Evolving exploration strategy to support future growth:
Since 2018, Aura's exploration strategy has focused on replacing depleted ounces across its core operating assets and increasing LOM (life of mine), while expanding production. During this time, combined proven and probable mineral reserves increased by 59 per cent, and combined measured and indicated mineral resources have increased by 194 per cent as result of investment in exploration increasing from about $8-million (U.S.) in 2018 to $22-million (U.S.) in 2022, taking advantage of over 650,000 hectares of underexplored mining rights across its portfolio.
- In 2022, Aura's exploration initiatives played an increasing role in its capital allocation strategy, forming a solid basis for future growth, including:
- 123,895 metres drilled across greenfield and brownfield projects.
- Increased mineral reserves and mineral resources, with over 100 per cent conversion of inferred mineral resources into measured and indicated mineral resources.
- New targets identified both surrounding mine workings and regionally across the portfolio, through soil sampling, mapping and geophysics.
- Important mineral rights acquisitions at EPP mines, to potentially expand the mineral footprint, and at Matupa, to test the regional potential.
- New projects were added to the exploration pipeline, including the Borborema project (located in Rio Grande do Norte, northeast Brazil), and the Serra da Estrela copper project in the prolific Carajas region, to support future growth in mineral resources and mineral reserves, and new discoveries.
Two thousand twenty-three objectives:
With a strong foundation and increased confidence in the exploration pipeline as result of successful exploration programs, especially in the last two years, Aura has increased its exploration budget for 2023 to between $22-million (U.S.) and $26-million (U.S.), and is planning an additional 110,000 metres of diamond drilling.
- The strategy for 2023 and beyond includes work intended to increase mineral resources and mineral reserves, developing earlier-stage targets, drill testing the regional potential of several assets, and allowing for future production expansion. The targeted programs for 2023 for select assets include:
- EPP: Increase mineral reserves through conversion of measured and indicated, and inferred mineral resources, so as to expand its LOM.
- Aranzazu: Testing the continuity of mineralization of GH at Aranzazu to expand LOM, and drilling in new potential deposits to build the foundation for a potential future increase in annual production.
- Matupa: Advancing regional targets in order to increase mineral resources inventories through the development of nearby deposits, mainly at Serrinhas.
- Aura Carajas: Conducting an initial exploration program at the newly acquired Serra da Estrela copper project to understand its potential and build a basis for a focused exploration program in 2024.
- Borborema: Feasibility study (FS) currently under way, expected to be published in Q3 2023.
Rodrigo Barbosa, president and chief executive officer of Aura, commented: "We are excited to share, for the first time, a comprehensive update on our exploration initiatives and growth plans across our portfolio. Exploration continues to play a significant part in our capital allocation strategy, with investments increasing significantly since 2018, to up to $26-million (U.S.) budgeted for 2023. Our priority over the years has been to more than replace our depleted ounces and generate cash flow, which we have successfully and consistently done. We believe we are now in a strong position to focus on growth for future years, by aggressively developing immediate and regional targets, and exploring our robust pipeline."
Mr. Barbosa continued: "We are proud of the unmatched exploration potential across our portfolio, with over 650,000 hectares and several new projects added to the pipeline. Many of our projects are located in prolific jurisdictions, including several productive mineral belts that have seen little to no modern-day exploration. We are excited about the prospect of using our strong cash flows to replace, define and discover new ounces. We have several immediate targets, particularly at the Aranzazu and EPP mines, that are expected to contribute to resource and reserve growth, and regional exploration across various projects to contribute to future new discoveries."
Aranzazu mine, Mexico
Aranzazu is an underground copper mine in operation, producing gold as a byproduct, located in a world-class polymetallic district where Aura controls approximately 11,000 hectares of mineral rights. To date, only 5 per cent of the mineral claims have been drilled. Mining activity in the area dates almost 500 years and it hosts multiple world-class deposits, including Tayahua (Minera Frisco SAB de CV), Camino Rojo (Orla Mining Ltd.) and Penasquito mine (Newmont Corp.). The Aranzazu deposit is characterized as an endo-skarn and exo-skarn deposit replaced in Mesozoic limestone strata.
Since the restart of operations in 2018, exploration efforts have focused on (i) extending the life of mine (LOM) and (ii) building the basis to allow for an increase in production capacity. As a result, Aura has been able to increase LOM from five years at the time of the restart to currently more than seven years, based on mineral reserves only. In addition, production capacity was expanded by 30 per cent during 2021.
In 2022, Aura invested approximately $7.5-million (U.S.) in exploration at Aranzazu, with 37,685 metres drilled, resulting in:
Substantial increase in MRMR:
- Current measured and indicated mineral resources (as of Dec. 31, 2022, inclusive of mineral reserves) includes 1.59 MGEO (million gold equivalent ounces), an increase of 12 per cent (170,000 GEO (gold equivalent ounces)) compared with 2018.
- Proven and probable mineral reserves of 852,000 GEO, an increase of 61 per cent (325,000 GEO) compared with 2018.
- Production capacity increased by 30 per cent in 2021.
Current exploration initiatives include multiple targets being advanced near existing mine infrastructure to support further increases in LOM. Aura has also made important advances in finding new deposits. The priority targets include:
Initiatives to increase LOM in the short term, such as at GHFW zone, where skarn mineralization was intercepted in a deeper hole indicating that the orebody is still open down dip.
- Initiatives to allow expansion of mineral resource and reserve, and potential increase in production in the medium term, such as:
Several small skarn pipes identified with surface exposures in northwest of Aranzazu mine, and may be a continuation of Aranzazu structure and possible connection zone toward the northwest.
- Drilling below historical underground workings at Cabrestante SW, Cata-Arroyo, Esperanza, Limestone Bridge and El Cobre tested the continuity and potential of mineralization down dip below mined areas. Drilling confirmed skarn alteration with low occurrence of sulphides. The drill holes demonstrated important geological information in all targets with indications that there may be economic mineralization, information which will be used for future targeting.
Regionally, geological mapping and sampling generated several early-stage targets, including new copper-gold skarns, manto-type polymetallic mineralization and high-grade gold/silver veins. Low-grade Au-Cu (gold-copper) porphyry mineralization could possibly occur as well.
For 2023, Aura intends to complete 29,400 metres of drilling, which will focus on testing the continuity of GH and Cabrestante areas, with the goal of increasing mineral resources and mineral reserve of existing deposits. In parallel, drilling is planned for El Cobre and Aranzazu extensions, a potential connection zone to find and delineate new skarn mineralization near-mine workings.
Ernesto and Pau-a-Pique mines, Brazil
EPP is located on the prolific Guapore belt in Mato Grosso, Brazil, and previously owned and operated by Yamana Gold. The belt has several historic mines but has seen very little modern-day exploration. Aura acquired EPP in 2016 and its land package includes 296,796 hectares along a 200-kilometre trend, which represents a dominant land position controlling most of the belt, and an excellent opportunity for growth.
EPP is located near Pontes e Lacerda and consists of multiple gold deposits: the Lavrinha open-pit mine, the Ernesto open-pit mine, the Pau-a-Pique underground mine (PPQ), the Japones open-pit mine and the Nosde open pit-mine. These deposits are composed of metasediments from a foreland basin folded and sheared under ductile-brittle conditions commonly in tectonic contact with the basement. Strong hydrothermal alteration associated with gold mineralization occurs in fault zones associated with the lower contact of the Aguapei group with the basement.
Current mineral reserves support a four-year LOM, and Aura is carrying out exploration work with the goal of extending the LOM in the short term as the orebodies remain open at depth and between the orebodies. In 2022, Aura spent approximately $8.7-million (U.S.) on exploration at EPP, with 56,053 metres drilled. Results have supported the exploration strategy, mainly:
Continued increase in resources, exceeding depletion, of 91 per cent.
Recent exploration successfully confirmed the connection between the Lavrinha and Nosde mines in the schist, and new areas around Ernesto pit, with further exploration and potential conclusions to happen during 2023.
Surface sampling and mapping were completed farther north of Pau-a-Pique, GP targets and the BP anomaly to better define the regional potential.
107 km of a ground magnetic survey and 10.5 km of IP ground survey were completed, with results indicating that the quartz veins associated with sulphides with surface exposure has continuity at depth in the BP target anomaly. This structure is similar to the PPQ mine structure and it is interpreted as new ore shoot with the same strike continuity.
For 2023, a significant portion of the exploration budget ($8-million (U.S.)) is expected to be used for work carried out at EPP, including 36,500 metres of drilling with the goal of:
- Converting inferred mineral resources to indicated mineral resources, and supporting increases in mineral reserves from Nosde-Lavrinha and additional near mine targets.
- Drilling will also target Japones West, a recently acquired area that has surface indications of similar mineralization as Lavrinha and Japones mines (mylontic schist). Of the regional targets, drilling is planned for 2023 at the BP anomaly.
San Andres mine, Honduras
San Andres is an open-pit heap leach gold mine located in the highlands of western Honduras, in the municipality of La Union, department of Copan, approximately 150 km southwest of the city of San Pedro Sula.
The San Andres deposit is classified as an epithermal gold deposit associated with extension structures within tectonic rift settings. Gold occurs in quartz veins predominantly composed of colloform banded quartz (generally chalcedony with lesser amounts of fine quartz, adularia, dark carbonate and sulphide material). Aura's district-scale land package includes 6,162 hectares with most of the exploration focused near mine.
Last year, Aura's exploration efforts focused on better understanding the alteration zones and recovery of production areas.
This involved a $600,000 (U.S.) budget with 5,966 metres drilled. Results were supported the exploration strategy and, in particular:
Infill drilling increased the confidence and filled the structural gaps in the alteration models at Esperanza and Banana Ridge targets.
Drilling at Esperanza expanded both measured and indicated mineral resources by 144,000 GEO.
Geochemical sampling (soil and rock) was performed in San Andres IV and geophysical work was in progress during Q4 2022 in the San Andres concessions.
In Q4 2022, a magnetic drone survey commenced to better define the 2023 program for SAIV, SAV and SAVII concessions. The survey concluded in late Q1 2023.
For 2023, 14,000 metres of drilling is planned, targeting:
Infill and alteration models at Esperanza with a focus on converting indicated mineral resources to measured mineral resources.
- Additional work to better define oxide-sulphide limits and to verify the potential of old waste dumps from areas that were mined historically with higher cut-off grades.
- Identify the continuity of quartz-carbonate veins in the sulphide zone at depth, which was identified in both recent and historical drilling. The sulphide zone is not part of current mineral resources and mineral reserves estimate at San Andres, and cannot be processed by the heap leach method.
Almas project, Brazil
The Almas project, which is located in the municipality of Almas, in Tocantins state, Brazil, is an open pit gold mine wholly owned by Aura. Almas is the first greenfield project constructed by Aura. In April, 2023, Aura announced the commencement of operations and ramp-up phase, with commercial production anticipated for Q3 2023.
The Almas project is located on the Almas greenstone belt, which is one of the lesser explored greenstone belts in Brazil, with less than 100,000 metres drilled, and has approximately 1,500 square km of greenstone belt rocks, a highly fertile geological terrain for gold mineralization. Other greenstone belts in Brazil with similar geology, such as Crixas, Rio Itapircuru and Iron Quadrangle, host meaningful deposits that have been the subject of considerable drilling campaigns. Aura believes that it could potentially find new deposits in the belt to feed the current plant in the upcoming years, with regional exploration.
The three main gold deposits that comprise the Almas project include Paiol, Cata Funda and Vira Saia, and are located along a 15 km long corridor on the Almas greenstone belt, a Paleoproterozoic volcano-sedimentary sequence which hosts numerous orogenic gold occurrences. The gold-mineralized zone occurs in the core of hydrothermal alteration zones, generally associated with variable amounts of quartz, carbonate, albite, sericite and sulphide minerals. The Almas project's claims consist, in addition to current deposits, of multiple early-stage exploration targets, including Nova Prata, Espinheiro, Jacobina, Morro do Carneiro, Olavo, Vieira and Jacare, in a total area of 224,141 hectares of mineral rights.
In 2022, Aura invested approximately $1.3-million (U.S.) in exploration activities at Almas, with 6,373 metres drilled. Results of such exploration activities included:
Nineteen targets defined through mapping and surface sampling.
Drilled five targets with positive results, including Morro do Carneiro, Ijui, Nova Prata, Quirino and Lagartixa.
Ijui target located between Cata Funda and Paiol deposits in the same host rock context (chlorite schist) intercepted hydrothermal alteration zones. Differently than observed at Paiol deposit, hydrothermal alteration zones in Ijucontain pyrite, chalcopyrite, galena and sphalerite.
Drilling was also completed at three new potential targets, all of which have similar characteristics to the Paiol-Cata Funda deposits, which require further follow-up.
Of the numerous targets defined, Aura believes that the most compelling is the Morro do Carneiro target, located two km east of the Cata Funda deposit. The gold mineralization is associated with shear zones in a meta chert rock. Delineation drilling was carried out in the main ore shoot identified during previous work, with nine drill holes concluded, totaling 2,321 metres. The drilling campaign confirmed the continuity of four mineralized lenses with an average of 100 metres length in strike and 160 metres down dip, real thickness varying from one m to 16 metres. Geological modelling and preliminary resource estimation exercises are under way to better define mineralized zones and future stepout drilling in the target.
The 2023 exploration plan for Almas includes 12,600 metres of drilling with a focus on infill drilling at Paiol to convert inferred mineral resources to indicated mineral resources. Stepout drilling will also be conducted at least other three regional targets.
Borborema project, Brazil
The Borborema project is a greenfield open pit gold project, located in the municipality of Currais Novos, Rio Grande do Norte state, in the northeast of Brazil. Aura acquired the project in September, 2022, and is currently completing a feasibility study. Upon completion of the FS, Aura expects to convert 1.87 million ounces of gold of JORC-compliant measured and indicated mineral resource, and an additional 570,000 ounces of gold of inferred mineral resource in National Instrument 43-101 mineral resources.
Matupa project, Brazil
The Matupa project is a gold project located in the northern part of the state of Mato Grosso, Brazil. This region contains several gold and base metal deposits around 50 km radius of the project. The project's claims consist of multiple exploration targets, in a total area of 62,500 hectares of mineral rights.
The Matupa project has three main deposits, including: X1 and Serrinhas (gold), and Guaranta Ridge (base metals). The X1 deposit was the main deposit which was delineated for feasibility study of Matupa gold project (see Aura's press release dated Oct. 3, 2022). The X1 deposit has 325,000 oz of measured and indicated mineral resources and 31,000 oz of inferred mineral resources. The project has 311,000 oz in proven and probable mineral reserves.
During 2022, exploration focused on the development of multiple targets near the X1 deposit, including Serrinhas, Target 47 and V6 zones, with exploration drilling to test geochemistry and magnetometry anomalies, and stepout drilling of previous positive results. A total of 75 drill holes were completed, totalling 17,818 metres. Advancements for each of the targets are listed below.
Serrinhas, which is located 22 km south of the X1, consists of 10 km northwest-trending hills with a series of former artisanal small pits, and large gold anomalies in the soil. Drilling at Serrinhas concentrated on the MP1 and MP2 targets, and confirmed the continuity of these targets along strike and down dip. Though the connection between MP2 East and MP2 West could not be well drilled due to environmental licence, directional drilling is planned for 2023 to further test the potential of this area.
Preliminary metallurgical studies and 1,100 km of drone magnetic geophysical survey were also carried out at Serrinhas. The mineralization in Serrinhas is associated with low mag anomalies and the survey is expected to provide new targets for exploration drilling. The preliminary metallurgical studies were completed, which confirmed the possibility to feed the X1 plant with Serrinhas's ore (94.5 per cent of recovery considering gravity concentration plus gravity tail leaching).
Target 47 is 1.5 km south of the X1 deposit and is a porphyritic-style mineralization target. Drilling tested the continuity at depth of the exploration drill holes completed in 2021, confirming mineralized high-grade zones inside porphyritic mineralization. Next steps of exploration work will concentrate on defining the higher-grade continuity of this corridor.
V6 target is located 20 km north of X1 deposit and it is in a trend of Guaranta Ridge epithermal system. In 2022, there were 573 soil samples collected to better detail previous soil campaign, and has confirmed the potential of copper, gold, lead, and zinc mineralization related to quartz veins with phyllic alteration halo in granites. Exploration drilling to test this area started in Q4 2022, with one drill hole completed, totalling 243 metres. The assays are still pending but were identified during the log occurrence of veins with chalcopyrite, pyrite, sphalerite and phyllic alteration.
For 2023, 15,000 metres of drilling is planned, with the primary focus on directional drilling and environmental licences to test connections between MP2 West and MP2 East at Serrinhas. The results of the drone magnetic survey are expected and will guide further exploration work. Additionally, exploration in Alto Alegre, GR and V6 targets. Aura strongly believes that continuation of exploration at Matupa can support increases in LOM beyond the disclosed feasibility report.
Aura Carajas, Brazil
Aura Carajas -- the Serra da Estrela project -- was recently acquired by Aura, to strategically support potential copper discoveries and the growing exploration pipeline. The project is located in the prolific Carajas region. The Carajas mineral province is one of the most important polymetallic districts in the world and hosts several IOCG (iron oxide-copper-gold) deposits, such as Sossego and Salobo mines (owned by Vale), Pedra Branca, Igarape Bahia-Alemao, Cristalino, Gameleira and Alvo 118. The project is a permitted exploration target of 9,805 hectares.
Mineralization targets are along a six km strike with a surface anomaly up to 500 parts per million (ppm) Cu. Prior work includes nine historical mineralized exploration holes totalling 2,552 metres, previously drilled by Anglo American. Aura intends to undertake exploration activities to test the continuity and economic grades of the target, with 8,000 metres of drilling planned for 2023, drilling which is expected to commence in the second semester and which results are expected by early 2024.
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 conform 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 2023 AIF and the applicable technical reports, copies of which are 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, an employee of Aura and a qualified person within the meaning of NI 43-101.
About Aura Minerals Inc.
Aura is focused on mining in complete terms -- thinking holistically about how its business impacts and benefits every one of its stakeholders: the company, its shareholders, its employees, and the countries and communities it 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 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, which is at the exploration stage.
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