The Zancudo Project is a gold and silver deposit located in the Republic of Colombia. The project is owned by Canadian junior Denarius Metals.
In January 2025, local environmental authority Corantioquia green lighted the Environmental Impact Study (EIS) for the project. Subsequently, Denarius commenced mining activities at the property in March 2025.
Zancudo is expected to achieve first production in the second quarter of 2025.
A new processing plant with a capacity of 1,000 tonnes per day (tpd), along with other site infrastructure, is expected to be completed by the end of 2025. This will enable the production of high-grade gold-silver (Au-Ag) concentrates.
Zancudo Project Location
Zancudo Project is located in the Municipality of Titiribí, Department of Antioquia, Republic of Colombia. The site is approximately 30km southwest of the city of Medellin.
The project area comprises three adjoining mining concession contracts and one exploration license with a total area of 1,054 hectares. The Zancudo Project is located near several large producers and benefits from access to labour, the Colombian national power grid, and ample water resources.
Situated approximately 190km from the Port of Buenaventura, the gold and silver project is being connected to a major highway leading to Medellin through a 4km bypass road.
Zancudo Project History
The Zancudo Project, which encompasses the historic Independencia Mine, has a legacy stretching back over 250 years. Gold was first discovered in the area in 1746.
The key player historically was Sociedad de Zancudo, which operated from 1848 to 1948, with peak mining years between 1863 and 1927. The mine ceased operations in 1945,
Total production from the district was estimated to be between 1.4 and 2 million ounces of gold equivalent from 1793 to 2006.
Gran Colombia Gold, later known as GCM Mining and a precursor to Aris Mining Corporation, acquired the Zancudo Project in 2010. The project was optioned to IAMGOLD Corporation in 2017, which conducted exploration until 2022 as part of their agreement.
In 2021, Denarius Metals acquired Zancudo Metals and the rights to the project from Gran Colombia Gold.
After IAMGOLD decided not to complete their earn-in under the option agreement for reasons unrelated to the project, Zancudo Metals retained full ownership and began developing the project.
Geology and Mineralisation
The Zancudo Project is situated on the western flank of the Central Cordillera in the Colombian Andes, separated from the Western Cordillera by the Cauca River.
The deposit is located within the Romeral terrane, an oceanic region consisting of metamorphosed mafic to ultramafic complexes, ophiolite sequences, and oceanic sediments likely dating from the Late Jurassic to Early Cretaceous period.
This terrane is partially overlaid by continental sediments from the Oligocene to Lower Miocene age, known as the Amagá Formation, which includes conglomerates, sandstones, shales, and coal seams.
Gold mineralisation is associated with the emplacement of porphyry stocks. The host rocks for gold mineralisation include the schists of the Arquía Complex, sedimentary rocks of the Amagá Formation, and Late Miocene andesite porphyry intrusions.
These sediments have been folded into multiple synclines intersected by high-angle reverse faults oriented N10-20°W with a steep dip of 50 to 70° east.
At Zancudo, mineralisation is found in multiple stacked mantos and steeper structures, which have been exploited over a strike length of 3,500m. The known vertical extent of the mineralisation reaches approximately 400m.
Mineral Resource Estimate
The current MRE for the Zancudo Project includes 4.1 million tonnes grading 6.5 g/t gold and 107 g/t silver totalling 860,000 ounces of gold and 14.1 million ounces of silver.
At a gold equivalent grade of 8.1 g/t, the MRE represents a total of 1.06 million gold equivalent ounces.
Mining and Processing
The 2023 preliminary economic assessment (PEA) for the Zancudo Gold-Silver mineral deposit outlines an underground mining strategy. The mineralisation occurs in near-vertical veins and flat-lying structures under mountainous terrain. Following the completion of the December 2022 Resource Block Model, eight distinct mining zones were identified.
These include five steeply dipping vein structures—Santa Catalina, Porvenir, Panal, Ortiz A, and Ortiz B—and four flat-lying mineralised structures, known as Manto Antiguo, Manto Antiguo Lower, Manto Inferior, and Miel.
Mine Stope Optimization (MSO) was applied to the block model to identify mineable stope blocks, and a mine plan was developed to extract these blocks.
The resue mining method is proposed for the veins, based on their orientation, width, historical mining practices, and geotechnical performance. This method involves using waste rock as backfill as the stope advances. It is highly selective, allowing for mining narrow widths down to 0.5m. The process includes developing an access drift, segregating mineralised material from waste, and executing overhand mineralisation extraction. The production schedule aims for 50 tonnes per day per heading due to the low productivity of resue stoping.
For the Mantos, a resue room and pillar design is proposed, developed on a grid basis. Pillar sizes are determined by geotechnical calculations and practical observations, with additional work required to ensure adequate dimensions. The Manto production schedule targets 100 tonnes per day per heading.
The PEA suggests processing mined material through three-stage crushing, conventional grinding, and slurry conditioning. This is followed by bulk sulphide flotation to recover gold and silver, with the concentrate thickened, filtered, and prepared for shipment.
Flotation tailings will be thickened and filtered for disposal as dry-stacked material in a tailings storage facility.