Guillermina Deposit, Nicaragua

Quick Facts

Ownership: 100%

Location: Nicaragua

Status: Advanced Exploration

Commodity: Gold

Mining Method: Underground

Guillermina Deposit

Guillermina is located on the Hemco Property in the Mining Triangle district centered around the towns of Bonanza, Rosita and Siuna in northeastern Nicaragua and is situated approximately four kilometres west of the Pioneer Mine.

It consists of a 1.8 km vein system oriented at an azimuth of 245° with notable anomalies in gold, silver, and zinc. The mineralization system includes an assemblage of hydrothermal breccias, stockwork, and veinlets up to 20 m in thickness, with a crustiform to colloform-banded quartz chalcedony-adularia matrix. The breccia matrix contains galena, sphalerite, and hematite occurring in patches and bands throughout.

Guillermina presents a promising opportunity that could significantly contribute to the future development of the Porvenir Project.

Reserves and Resources

Guillermina Deposit Mineral Resource Statement (effective March 31, 2025)

Classification	Cut-Off	Tonnes	NSR	Grade				Contained Metal
Classification	NSR Value	(kt)	$/t	Ag (g/t)	Ag (g/t)	Zn (%)	AuEq (g/t)	Au (koz)	Ag (koz)	Zn (Mlb)	AuEq (koz)
Indicated	$82.50/t	1,286	142	0.71	23.3	6.6	3.13	30	962	187	129
Inferred	$82.50/t	1,286	155	1.32	30.2	5.73	3.66	55	1,250	162	152

Table Notes:

Mineral Resources are classified according to the Canadian Institute of Mining Metallurgy and Petroleum’s “CIM Definition Standards for Mineral Resources and Mineral Reserves” adopted on May 10, 2014 (the “CIM Standards”).
The Mineral Resources have been reported within underground reporting shapes generated with Deswik Stope Optimizer using a net smelter return (“NSR”) cut-off value of $82.50/t and a minimum mining width of 1.0 m.
Material within 30 m of the topographic surface has been excluded from the Guillermina Mineral Resources to allow for artisanal mining.
Mineral Resources are estimated using a long-term gold price of $1,700/oz Au, a silver price of $20/oz Ag, and a zinc price of $1.36/lb Zn.
Metallurgical recoveries are applied on a block-by-block basis with an average of 85.5% for gold, 30.7% for silver, and 91.0% for zinc.
The NSR $/t value for each block was calculated using the following NSR factors:
-  $53.12 g/t Au x gold recovery
-  $0.41 g/t Ag x silver recovery
-  $1,755.54 % Zn x zinc recovery
The formula used to calculate the AuEq grade is Au g/t + (Ag g/t * silver AuEq factor) + (Zn% * zinc AuEq factor), where:
- silver AuEq factor = (0.41 * silver recovery) / (53.12 * gold recovery)
- zinc AuEq factor = (1,755.54 * zinc recovery) / (53.12 * gold recovery)
Average bulk density is 2.71 t/m3.
Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
Mineral Resource estimate assumes underground mining and extends from surface to a depth of 400m.
Numbers may not add or multiply due to rounding.

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