Overview

Mine Type	Underground
Status	Active
Commodities	Gold
Mining Method	Longitudinal stoping Transverse stoping Transverse open stoping
Backfill type	...
Production Start	...
Mine Life	...
Snapshot	New Liberty is the key asset in Avesoro Resources’ portfolio and stands as Liberia’s first and largest commercial gold mine. The New Liberty operation consists of two worked-out open pits, an underground mine with three separate portals, and a large processing plant supported by tailings dams. The open pit operations, which lasted from October 2014 was completed in June 2022.The underground mining operation, which began in August 2020, features three distinct declines: Larjor, Kinjor, and Marvoe. Avesoro Holdings Ltd., a private equity firm, acquired the mine in December 2018. Mine operations data has not been publicly available since then.

Deposit type

• Orogenic
• Vein / narrow vein

Summary:

The New Liberty Property hosts a typical Upper Archean to lower Proterozoic style of metallogeny, characteristic of greenstone-hosted lode gold mineralisation, where deposits are often referred to as orogenic, and characterised by the presence of gold-quartz veins and disseminated mineralisation. Gold mineralisation is hosted in moderate to steeply dipping quartz-dominated shear zones with associated extensional vein systems. This model is consistent with Archean orogenic gold deposits described by Hagemann and Cassidy (2000), Richards and Tosdal (2001), Goldfarb et al. (2001) and Roberts et al. (1989).

The New Liberty deposit is hosted in sheared and altered ultramafic rocks. The gold mineralisation is associated with disseminated sulphides. The disseminated sulphide host bodies are more conOnuous than a typical quartz hosted vein. The orebody is in a highly sheared and myloniOsed schist belt which trends east-southeast.

The average dip of the orebody is approximately 60°, with local variations in dip ranging from near vertical to around 40°. The orebody consists of a number of veins, generally parallel to each other. Mineralisation can occur in more than one of the veins, creating the potential for multiple parallel stopes in some parts of the deposit.

The widths of the mineralised zones range from 2 m to 30 m, with an average width of 10 m.

Within the ultramafic unit, silicification is found proximal to the mineralisation, within the immediate hangingwall and rarely in the footwall gneisses. Other alteration styles associated with the mineralisation include the presence of phlogopite as well as chlorite within the mineralised zone, and an associated sulphidic bleaching of the rocks linked with the destruction of magnetite.

These features point to a pathway for the mineralising fluids which was active over a long period of time. The deposit shows the classic signs of sulphidation, with iron sulphides (mainly pyrrhotite) replacing the magnetite and it has a low sulphide content with sulphides forming between 0.1% and 1% of the mineralised zones.

Multi element analyses of cores have highlighted a clear association between gold and arsenic, sulphur, nickel and tungsten in the mineralised zones. Enhanced values of magnesium, sodium, potassium, rubidium and barium occur along the margins of the mineralisation. It is hypothesised that the gold-bearing metamorphic fluid may include a granitic component in its evolution.

Vast majority of the mineralisation at the Project is hosted within the altered parts of the sheared ultramafic rocks. Pyrrhotite, gersdorffite and arsenopyrite are the main sulphides with occasional pyrite and rare chalcopyrite or pentlandite. Metallurgical tests of the mineralised sections carried out by Lakefield Research Limited (Lakefield, 1999b) indicated that the gold is free in form. Gold mineralisation occurs in zones of variable thickness, with average widths of 10 m, and is nearly continuous along 2 km of strike.

Mining Methods

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Comminution

Crushers and Mills

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Processing

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Production

Commodity	Units	2023	2018	2017	2016
Gold	koz	....	110	76	64

Operational metrics

Metrics	2023	2018	2017	2016
Plant annual capacity	....		1.1 Mt
Tonnes processed	....	1,411 kt	1,144 kt	842 kt
Stripping / waste ratio	....	16.1	11.1	9
Ore tonnes mined	....	1,352 kt	1,166 kt	996 kt
Waste OP	....	21,797 kt	12,935 kt	8,965 kt
Total tonnes mined	....	23,149 kt	14,102 kt	9,961 kt

Personnel

Job Title	Name	Profile	Ref. Date
.......................	.......................		Sep 21, 2024
.......................	.......................		Sep 21, 2024
.......................	.......................		Sep 22, 2024
.......................	.......................		Sep 22, 2024
.......................	.......................		Sep 22, 2024
.......................	.......................		Sep 22, 2024