Aura Minerals Announces the Results of the Preliminary Economic Assessment for the Era Dorada Project

Rhea-AI Summary

Aura Minerals announced the Preliminary Economic Assessment (PEA) for its Era Dorada Project in Guatemala, acquired from Bluestone Resources in January 2025. The project boasts Indicated Mineral Resources of 1.9M oz gold at 9.31 g/t, with projected total production of 1.4M oz over 17 years LOM. Key financial metrics include initial capex of $264M, after-tax NPV of $485M at $2,410/oz gold price, and IRR of 24%. The underground mine project expects average production of 91k oz gold annually in the first 4 years with cash costs of $1,072.4/oz. Located near Asunción Mita, the project benefits from good infrastructure, accessibility via Pan-American Highway, and proximity to trained labor force. The deposit is a low-sulphidation epithermal gold-silver system with high-grade vein and low-grade disseminated mineralization.

Positive

• Strong resource base with 1.9M oz of high-grade gold (9.31 g/t) in Indicated category
• Robust economics with $485M after-tax NPV and 24% IRR
• Relatively quick payback period of 3.5 years
• 17-year mine life with steady production profile
• Good infrastructure and accessibility via Pan-American Highway
• High metallurgical recoveries of 96% for gold

Negative

• Significant initial capital requirement of $264M
• Project located in Guatemala, which may present geopolitical risks
• 5% government royalty on gross revenues
• High cash costs at $1,072.4/oz

ROAD TOWN, British Virgin Islands, June 09, 2025 (GLOBE NEWSWIRE) -- Aura Minerals Inc. (TSX: ORA, B3: AURA33, OTCQX: ORAAF) (“Aura” or the “Company”) is pleased to announce that the Company has filed a preliminary economic assessment for the Company’s wholly owned Era Dorada Project (“Era Dorada” or “Project”, which project was previously known as the Cerro Blanco Project), in the United States in accordance with S-K 1300.¹

In January 2025, Aura completed the acquisition of Bluestone Resources Inc. (“Bluestone”), which was the 100% owner of Era Dorada (or Cerro Blanco as it was known then), located in Jutiapa, Guatemala, near the town of Asunción Mita and border with El Salvador. Please see our press release dated January 13, 2025 for additional information on the acquisition.

Highlights:

• Indicated Mineral Resources of 1.9 million ounces of gold, assuming 6.35 million tonnes at 9.31 grams per tonne.
• Total production of approximately 1.4 million ounces of gold over a 17 years Life of Mine (“LOM”).
• Average production of 91k ounces of gold for the first 4 years.
• Total initial implementation capex of approximately US$264 million with a payback in approximately 3.5 years after the beginning of the operation.
• After-tax Net Present Value (“NPV”) of US$485 million when using the weighted average consensus gold prices for the projected period of US$ 2,410 per ounce.
• After-tax Project IRR of 24% when using the weighted average consensus gold prices for the projected period.
• US$ 1,072.4/oz average Cash Cost.
  

Main assumptions used for the base:

• Gold price (per ounce): US$ 2,410
• Exchange rate (GTC/USD): 7.75
• Guatemalan Government Royalty: (% of gross revenues): 5%
• Income taxes: 25%
• Discount rate: 5%
  

Rodrigo Barbosa, President and CEO of Aura, comments: "We are excited to announce the Preliminary Economic Assessment (PEA) for Era Dorada, a key addition to our portfolio of development projects acquired early this year. Following our approach with the development of Almas and Borborema projects, we are actively collaborating with local authorities and government agencies to ensure Era Dorada meets the highest environmental and social standards under our Aura 360 culture. The PEA delivers strong economics for the licensed underground project, with a Capex of US$ 264 million, an after-tax NPV of US$ 485 million and an unleveraged after-tax IRR of 24% at a gold price of US$2,410 / Oz.”

The Era Dorada PEA contemplates the potential development of Era Dorada as an underground mine.

Era Dorada Project

The Project is located in southeast Guatemala, in the Department of Jutiapa, approximately 160 km by road from the capital, Guatemala City and approximately 9 km west of the border with El Salvador. The nearest town to the Project is Asunción Mita, a community of about 18,500 people situated approximately 7 km west of the Project. The exploitation license covers 15.25 km² and lies entirely in the municipality of Asunción Mita. Era Dorada is not considered to be a property material to Company for the purposes of NI 43-101.

The Era Dorada Project site is accessible year-round via the Pan-American Highway (CA1) through Asunción Mita, with flat to rolling hill topography. The climate is tropical dry forest, with elevations of 450–560 masl, a wet season from May to October, 1,350 mm annual rainfall, temperatures ranging from 10°C to 41°C, 2,530 mm annual pan evaporation, and 62% average humidity. The site is near communities, including Asunción Mita (18,500 population), and the La Baranca power substation (20 MW capacity) a few kilometers south. No prior mining exists in the area, but the closure of Goldcorp’s Marlin Mine in 2017 provides access to trained Guatemalan labor. The project plans to hire locally, with training costs included in the budget.

	Gold prices (US$/oz)
		-20%	-10%	0%	+10%	+20%
		1,928	2,169	2,410	2,651	2,892
After-tax Project NPV	US$ million	171	328	485	643	800
After-tax Project IRR	% p.a.	12%	18%	24%	29%	34%

Geology, Mineralization and Drilling

The Era Dorada was identified by Mar-West by sampling of densely silicified boulders. In October 1998, Mar-West’s holdings in Honduras and Guatemala were purchased by Glamis Gold Ltd. In November 2006, Goldcorp Inc. became the sole proprietor of the Project through the purchase of Glamis Gold. Goldcorp undertook a comprehensive exploration program from 2006-2012 including additional surface exploration, over 3.4 km of underground development, and 43,016 meters of surface and underground drilling. On January 4, 2017, Bluestone entered into an agreement with Goldcorp to acquire 100% of the Project.

As of the end of 2021, Bluestone had drilled approximately 267 holes for a total of 45,725 m on the property since the acquisition from Goldcorp. The Era Dorada Gold Project is a low-sulphidation epithermal gold-silver deposit in the Cerro Blanco district, part of a Miocene-Pliocene volcanic arc in Central America. It features high-grade vein and low-grade disseminated mineralization. High-grade mineralization occurs in the Mita unit as two vein swarms (North and South Zones) with over 60 veins, merging into basal feeder veins, and is concealed by the 100 m thick Salinas Unit of volcanogenic sediments and sinters. Low-grade mineralization is hosted in silicified conglomerates and dacite/rhyolite domes within the Salinas cap rocks. The deposit includes high and low-angle chalcedony-quartz veins with bonanza-grade gold, particularly where adularia is prominent, over a 400 m vertical profile (150–450 masl). Calcite-dominated veins mark the mineralization limit at depth, with some high-gold values in silicified structures.

The Salinas Group includes thin hot spring deposits linked to underlying gold-silver quartz veins. The deposit lies under a 400 m x 920 m hill, with gold-bearing structures extending 2 km northwest within a hydrothermal alteration zone. Drilling shows significant intercepts, e.g., 203.8 m at 2.3 g Au/t and 8.1 g Ag/t (CB20-420) and 87.2 m at 5.9 g Au/t and 32.5 g Ag/t (UGCB18-89). Gold and silver deposition occurred via multi-stage veining with “crack and seal” pulses and boiling/flashing events near the paleosurface. Approximately 99% of gold is in electrum, with minor native gold and kustelite. The deposit’s pristine nature is indicated by minimal post-mineral displacement and a +400 m vertical grade profile.

Discovered by Mar-West in 1998 through silicified boulder sampling, the project was acquired by Glamis Gold, then Goldcorp in 2006, which conducted extensive exploration (2006–2012), including 43,016 m of drilling and 3.4 km of underground development. Bluestone acquired the project in 2017. As of the end of 2021, Bluestone had drilled approximately 267 holes for a total of 45,725 m on the property since the acquisition from Goldcorp.

Summary of Drilling

Year	Company	Holes Drilled	Meters
1998	Mar-West	9	1,340
1999	Glamis	48	7,074
2000	Glamis	18	3,525
2002	Glamis	23	6,525
2004	Glamis	42	9,370
2005	Glamis	120	29,065
2006	Glamis	67	15,129
2007	Goldcorp	47	12,373
2008	Goldcorp	2	586
2009	Goldcorp	1	140
2010	Goldcorp	10	2,277
2011	Goldcorp	28	5,898
2012	Goldcorp	96	21,370
2017	Bluestone	8	2,324
2018	Bluestone	74	13,993
2019	Bluestone	61	8,403
2020	Bluestone	74	15,172
2021	Bluestone	50	5,833
Total		778	160,397

Mineral Resource Estimates

The Era Dorada Gold Project is a low-sulphidation epithermal gold-silver deposit with high-grade vein and low-grade disseminated mineralization. High-grade mineralization in the Mita unit forms two vein swarms (North and South Zones) merging into basal feeder veins, with intercepts like 15.5 m at 21.4 g Au/t and 52 g Ag/t. Bonanza grades are associated with ginguru banding and carbonate replacement textures, with <3% sulphide content. Low-grade mineralization (0.3–3.0 g Au/t) surrounds high-grade veins. The Mita rocks are overlain by the 100 m thick Salinas unit, hosting low-grade mineralization (0.3–1.5 g Au/t) in silicified conglomerates and rhyolite breccias. Exploration follows CIM Mineral Exploration Best Practice Guidelines (2019).

The resource estimate by Garth Kirkham, P. Geo., conforms to CIM standards, with 130,307 gold assays (153,078 m, 0.68 g/t average) and 130,238 silver assays (153,003 m, 3.75 g/t average). Bulk density is assigned by lithology and vein on a block-by-block basis.

The estimate was completed using MineSight™ software using a 3D block model (5 m by 5 m by 5 m and 1 m by 1 m by 1 m sub-blocks). Interpolation parameters have been derived based on geostatistical analyses conducted on 1.5-meter composited drill holes. Block grades have been estimated using ordinary kriging (OK) methodology and the mineral resources have been classified based on proximity to sample data and the continuity of mineralization in accordance with NI 43-101, CIM’s “Definition Standards for Mineral Resources and Mineral Reserves” dated May 19, 2014, and “CIM Estimation of Mineral Resources and Mineral Reserves Best Practice Guidelines” dated November 29, 2019.

Resource Estimate using 2.25 g Au/t Cut-off

Resource Category	Tonnes (kt)	Au Grade (g/t)	Ag Grade (g/t)	Contained Gold (koz)	Contained Silver (koz)
Measured
Indicated	6,349	9.31	31.54	1,901	6,439
Measured & Indicated	6,349	9.31	31.54	1,901	6,439
Inferred	605	6.02	19.68	117	383

Notes:

1. Mineral Resources are reported in in accordance with NI 43-101.
2. Mineral resource estimates have been prepared by Garth Kirkham, P.Geo., a Qualified Person as defined by NI 43-101.
3. The Mineral Resource estimate is reported on a 100% ownership basis.
4. Underground mineral resources are reported at a cut-off grade of 2.25 g Au/t. Cut-off grades are based on a assumed metal prices of US$2,500/oz gold and US$28/oz silver, and assumed metallurgical recovery, mining, processing, and G&A costs.
5. Mineral Resources are reported without applying mining dilution, mining losses, or process losses.
6. Resources are constrained within underground shapes based on reasonable prospects of economic extraction, in accordance with NI 43-101. Reasonable prospects for economic extraction were met by applying mining shapes with a minimum mining width of 2.0 m, ensuring grade continuity above the cut-off value, and by excluding non-mineable material prior to reporting.
7. Metallurgical recoveries reported as the average over the life of mine and are assumed to be 96% Au and 85% Ag, respectively.
8. Bulk density is estimated by lithology and averages 2.47, 2.57 and 2.54 g/cm3 for the Salinas, Mita and mineralized vein domains, respectively.
9. Mineral resources are classified as Indicated, and Inferred based on geological confidence and continuity, spacing of drill holes, and data quality.
10. Effective date of the mineral resource estimate is December 31, 2024.
11. Tonnage, grade, and contained metal values have been rounded. Totals may not sum due to rounding.
12. Mineral resources are not mineral reserves and do not have demonstrated economic viability.

In addition, there has been mixed grade material mined during the creation of the extensive, existing ramp network which has been stockpiled adjacent to North Ramp entrance. The table shows the volume and tonnage based on an unconsolidated specific gravity of 2.0 gm/cm³ along with gold and silver grades and metal content. These resources are classified as measured.

Stockpile Resource Estimate (Measured Resource)

Volume (BCM)	Mine (t)	Au (g/t)	Ag (g/t)	Au (oz)	Ag (oz)
14,863	29,726	5.35	22.59	5,108	21,590

Notes:

1. Mineral Resources are reported in in accordance with NI 43-101.
2. Mineral resource estimates have been prepared by Garth Kirkham, P.Geo., a Qualified Person as defined by Ni 43-101.
3. The Mineral Resource estimate is reported on a 100% ownership basis.
4. Mineral Resources are reported without applying mining dilution, mining losses, or process losses.
5. Resources are constrained within bounding surfaces based on reasonable prospects of economic extraction, in accordance with NI 43-101.
6. Reasonable prospects for economic extraction were met by applying mining shapes with a minimum mining width of 2.0 m, ensuring grade continuity above the cut-off value, and by excluding non-mineable material prior to reporting.
7. Metallurgical recoveries reported as the average over the life of mine and are assumed to be 96% Au and 85% Ag, respectively.
8. Bulk density is estimated f at 2.00 g/cm3 for the Stockpile material.
9. Mineral resources are classified as Measured based continuity, spacing of drill holes and data quality.
10. Effective date of the mineral resource estimate is December 31, 2024.
11. Mineral resources are not mineral reserves and do not have demonstrated economic viability.
    

Qualified Persons

The technical content of this press release has been reviewed and approved by the QPs who were involved with preparation of the Era Dorada PEA study: Garth Kirkham, P.Geo., Homero Delboni Jr. and Porfririo Cabaleiro Rodriguez.

QPs are not aware of any known political, legal, environmental or other risks that could materially affect the project development.

About Aura 360° Mining

Aura is focused on mining in complete terms – thinking holistically about how its business impacts and benefits every one of our stakeholders: our company, our shareholders, our employees, and the countries and communities we serve. We call this 360° Mining.

Aura is a company focused on the development and operation of gold and base metal projects in the Americas. The company's five operating assets include the Minosa gold mine in Honduras; the Almas, Apoena, and Borborema gold mines in Brazil; and the Aranzazu copper, gold, and silver mine in Mexico. Additionally, the company owns Era Dorada, a gold project in Guatemala; Tolda Fria, a gold project in Colombia; and three projects in Brazil: Matupá, which is under development; São Francisco, which is in care and maintenance; and the Carajás copper project in the Carajás region, in the exploration phase.

For further information, please visit Aura’s website at www.auraminerals.com or contact:

Investor Relations
ri@auraminerals.com
www.auraminerals.com

Forward-Looking Information

This press release contains “forward-looking information” and “forward-looking statements”, as defined in applicable securities laws (collectively, “forward-looking statements”) which may include, but is not limited to, statements with respect to the activities, events or developments that the Company expects or anticipates will or may occur in the future. Often, but not always, forward-looking statements can be identified by the use of words and phrases such as “plans,” “expects,” “is expected,” “budget,” “scheduled,” “estimates,” “forecasts,” “intends,” “anticipates,” or “believes” or variations (including negative variations) of such words and phrases, or state that certain actions, events or results “may,” “could,” “would,” “might” or “will” be taken, occur or be achieved.

Known and unknown risks, uncertainties and other factors, many of which are beyond the Company’s ability to predict or control, could cause actual results to differ materially from those contained in the forward-looking statements. Specific reference is made to the most recent Annual Information Form on file with certain Canadian provincial securities regulatory authorities for a discussion of some of the factors underlying forward-looking statements, which include, without limitation, volatility in the prices of gold, copper and certain other commodities, changes in debt and equity markets, the uncertainties involved in interpreting geological data, increases in costs, environmental compliance and changes in environmental legislation and regulation, interest rate and exchange rate fluctuations, general economic conditions and other risks involved in the mineral exploration and development industry. Readers are cautioned that the foregoing list of factors is not exhaustive of the factors that may affect the forward-looking statements. All forward-looking statements herein are qualified by this cautionary statement. Accordingly, readers should not place undue reliance on forward-looking statements. The press release includes forward-looking statements relating, but not limited to, the following: the filing of the Era Dorada PEA and the timing of same; the preparation of a full Feasibility Study for Era Dorada and the timing of same; collaboration with local authorities and governmental agencies; economic viability of Era Dorada; evaluation of alternative mining methods for Era Dorada; the operation of Era Dorada; and mineral resource estimates.

The Company undertakes no obligation to update publicly or otherwise revise any forward-looking statements whether as a result of new information or future events or otherwise, except as may be required by law. If the Company does update one or more forward-looking statements, no inference should be drawn that it will make additional updates with respect to those or other forward-looking statements.

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¹ The Company does not consider Era Dorada to be a property material to Aura for the purposes of National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI 43-101”).

FAQ

What are the key financial metrics of Aura Minerals' (ORAAF) Era Dorada Project?

The Era Dorada Project has an after-tax NPV of $485M, IRR of 24%, initial capex of $264M, and a 3.5-year payback period, based on a gold price of $2,410/oz.

What is the resource estimate for Aura Minerals' Era Dorada gold project?

The Era Dorada Project has Indicated Mineral Resources of 1.9 million ounces of gold at 9.31 g/t, with additional Inferred Resources of 117,000 ounces at 6.02 g/t.

What is the expected production and mine life for ORAAF's Era Dorada Project?

The project expects total production of 1.4 million ounces of gold over a 17-year mine life, with average production of 91,000 ounces annually in the first 4 years.

Where is Aura Minerals' Era Dorada Project located?

The Era Dorada Project is located in southeast Guatemala, Department of Jutiapa, approximately 160 km from Guatemala City and 7 km from Asunción Mita.

What are the operating costs for the Era Dorada Project?

The project has an average Cash Cost of $1,072.40 per ounce of gold, with a 5% government royalty on gross revenues and 25% income tax rate.