Overview

Mine Type	Underground
Stage	Construction
Commodities	Zinc Lead Silver
Mining Method	Mechanized Cut & Fill Longhole stoping Shrinkage stoping
Mine Life	...
Snapshot	The El Mochito Expansion Project involves the optimization and expansion of the El Mochito mine. The Project includes: - Installation of internal underground mine shaft - Installation of a new 442-m subvertical (or internal, vertical) rock-only hoisting shaft; modification to the ventilation system; and extension of the communication system further into the mine as it progresses. -Upgrading of the underground pumping and water management system; -Upgrading the Process Plant - Replace flotation cells and filters; upgrading the crushing circuit, crusher feed wash plant to increase processing to 2,800 metric tonnes/day; -Increasing Tailings Dam Capacity. The El Mochito mine has benefited from significant reinvestment including new mining equipment, new flotation cells and a new shaft currently under construction.

Deposit type

• Manto
• Skarn

Summary:

Zinc-lead-silver mineralization of economic interest at El Mochito occurs in association with calc-silicate bearing skarn intervals hosted by limestone and calcareous shale of the Upper and Lower Atima Formation, in calcareous units of the Atima Formation’s main subunit, the Mochito Shale, in calcareous siltstone and shale of the Cantarannas Formation and in quartz-rich sandstones and siltstones of the siliciclastic-dominated Todos Santos Formation, which underlies the Cantarannas Formation. The stratigraphic section within which economic mineralization occurs at El Mochito slightly exceeds 1,250 m in true thickness.

Mineralization consisting of sphalerite, galena, argentite, tetrahedrite, acanthite, pyrrhotite and magnetite is associated with garnet and pyroxene skarn zones that are both structurally and stratigraphically controlled. The distribution of skarn directly reflects the geometry of the complex graben-related fault systems that channeled hot hydrothermal fluids through graben fill sequences to sites where they selectively reacted with calcareous wall rock to create siliceous, garnet and pyroxene-dominated skarn. Introduction of zinc-lead-silver mineralization on existing skarn zones reflects continued capacity of the graben’s fault systems to conduct the large volumes of hydrothermal fluid necessary to create this district’s high metal endowment.

Two main styles of zinc-lead-silver mineralization are present at El Mochito, these being mantos and chimneys, both of which show genetic association with hydrothermal fluid controlling fault systems. The largest mantos occur as stratabound replacement zones within the Lower Atima Formation, near its lower contact with the calcareous Cantarannas Formation. Manto style mineralization is also encountered in the central portion of the Atima Formation, along the upper and lower contacts of the Mochito Shale unit, typically adjacent to large chimney structures, and also within quartz rich clastic sediments of the Todos Santos Formation.

Chimney-style mineralization occurs as pipe-like accumulations of sulphides and associated skarn assemblages that are discordant to stratigraphy, often at high angles, and are spatially controlled by discrete zones of structural ground preparation which typically coincide with fault intersection zones or with dilational zones related to orientation changes or transfer zones along strike slip or dip slip fault systems. Chimneys at El Mochito are frequently rooted in zones of well-developed manto mineralization at the base of the Atima Formation and extend upward through that formation for substantial vertical intervals, with some passing through the Mochito Shale and onward to near surface elevations.

Manto and chimney deposits differ in their metal grade characteristics, with higher zinc lead and silver values and massive to submassive sulphide zones being more commonly seen in chimneys.

Mining Methods

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Comminution

Crushers and Mills

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Processing

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Production

Operational metrics

Personnel

Job Title	Name	Profile	Ref. Date
.......................	.......................		Nov 8, 2024
.......................	.......................		Nov 8, 2024
.......................	.......................		Nov 8, 2024
.......................	.......................		Nov 8, 2024

Total Workforce	Year
......	2019