Overview

Mine Type	In-Situ
Stage	Construction
Commodities	Lithium Potash
Mining Method	Brine mining
Production Start	...
Mine Life	...
Snapshot	At a proposed production of 20,000t LCE per year, there is potential for a “mine life” of up to 190 years. Construction at Mariana commenced in June 2022 and has advanced materially with brine deposited into the brine ponds in late 2022. Works on the brine ponds, brine wells, chemical plants, photovoltaic and other infrastructure facilities are progressing smoothly according to Ganfeng.

Deposit type

• Brine
• Evaporite

Summary:

Deposit Types
Evaporites and brines form a group of industrial mineral deposits where the commercially valuable commodities are either in solution (brines) or are potentially soluble (evaporites) with the addition of water. This style of deposit typically shows broad lateral continuity, but narrow vertical extents.

Brines are found throughout the Andes region in closed basins (salars) where inflowing waters containing low concentrations of metal are concentrated over time due to evaporation, until they become saturated and begin to precipitate out to form evaporites. Various thermodynamic constraints determine the order in which minerals precipitate.

The Mariana Project is a typical salar brine, containing lithium, potassium and boron within permeable aquifers.

Mineralization
The mineral commodities sought at the Mariana Project are metal ions dissolved within brines. Lithium salts are much more soluble than potassium and sodium, which tend to precipitate forming halite units.
The brines are subject to hydrogeological flow regimes allowing replenishment of brines that are extracted from the system.

The observation of brine within all drillholes across Salar de Llullaillaco basin suggests the existence of a connected unconfined brine-bearing system. The spatial distribution of lithology, lithological description and grain size distribution plus other associated elements, such as secondary porosity, were the most relevant aspects that led Geos to define a hydrogeological conceptual model that apportions the brinebearing complex into, at least, eight lithology sequences within the interconnected unconfined aquifer. Determination of the dominant aquitards (semi-impermeable lithologies with very low hydraulic
conductivity) within those units was then undertaken on a similar basis.

The following information was used for definition of the conceptual mineralization model:
• RC and DDH lithological logging, in particular lithology and grain size description
• Geophysical down hole electrical survey data
• TEM survey modelling for correlation with down hole geophysics and between drillholes
• Flow records profile for drillholes
• Geochemistry profiles from drillholes
• Effective porosity analyses of selected samples from 14 diamond drillholes

Mineralization of interest consists of lithium-enriched brines. Lithium (Li) and other potentially economic elements, potassium (K) and boron (B), are interpreted to be leached from volcanic rocks primarily by hydrothermal solutions emanating from deep-seated basin bounding faults and adjacent volcanoes. This also involves circulation of meteoric waters within proposed fault systems and through active stream and spring input flow into the salar.

Based on the drill information, the brines within the project area are interpreted to cover an area of about 135km2 , with an approximate length of 15km, width of 9km, and extend from depths from about
0.5m to at least 329m. Within the area drilled, host lithology sequences and brines show good continuity between drillholes. However, total porosity and the important specific yield porosity of the host
sequence lithologies have not been confirmed sufficiently at the current drillhole sampling.

Brine sampling and pumping tests indicate that two connected primary aquifers are at play in the salar, a middle aquifer within the volcanoclastic lithological units and an upper secondary porosity aquifer in the overlying halite evaposedimentary sequence. A lower aquifer in the sulfate – halite evaporite sequence also is projected to occur. Limited information is available upon which to support a reliable
characterization of this lower aquifer. However, this is anticipated to have much lower potential to be a productive aquifer.

Mining Methods

- subscription is required.

Comminution

Crushers and Mills

- subscription is required.

Processing

- subscription is required.

Production

Personnel

Job Title	Name	Profile	Ref. Date
.......................	.......................		Nov 15, 2018
.......................	.......................		Nov 15, 2018
.......................	.......................		Nov 15, 2018

Total Workforce	Year
......	2018