Overview

Mine Type	Open Pit
Status	Active
Commodities	Gold
Mining Method	Truck & Shovel / Loader
Production Start	...
Mine Life	...
Snapshot	The Bibiani Mine has completed its commissioning, with the first gold pour announced on July 7, 2022. Gold production ramp-up is progressing, to produce 225 to + 340Koz/ year through 2032 (with underground mining to commence 2025).

Deposit type

• Mesothermal
• Breccia pipe / Stockwork
• Vein / narrow vein

Summary:

The gold deposits at Bibiani are structurally controlled mesothermal lode-type deposits. The mineralization is associated with quartz veins and quartz stockworks which are hosted within a sequence of Lower Birimian fine to medium grained turbiditic sandstones. The sedimentary turbidite sequence is tightly folded, with west-dipping axial planes and localised development of steep west-northwest dipping shear zones which have acted as conduits for the initial gold mineralization. Gold is closely associated with arsenopyrite and pyrite. Sericite alteration is also commonly observed, both along mineralized structures, and associated with the felsic intrusives. High-grade veins often occur within graphitic shales which generally contain significant sedimentary/metamorphic pyrite.

The Bibiani deposit is hosted within a thick sequence of fine-grained graded turbidites with localised thin interbeds of fine to medium- grained turbiditic sandstones. The orebody is a mesothermal lode type deposit which is similar to the lode deposits in the Konongo Axim belt hosting the significant Obuasi deposit. The Bibiani orebody geometry is structurally controlled by a steep, north to north-east trending shear corridor 200 - 400m wide, within Lower Birimian sediments and close to the \ eastern contact of the Upper Birimian. The shear zone includes quartz infill as massive veins and quartz stock works. In the widest parts of the orebody, two and locally three individual quartz reefs or lodes can be identified. Two highly graphitic fault zones, historically referred to as pug seams or fissures, are associated with the major shear zone on footwall and hanging wall sides.

In general, the orebody dips east at 60 - 80°, crossing the regional structure at acute angles. At the centre of the mine the orebody alignment is 030 - 035° which changes to around 020° at the northern end of the mine. The strike of the bedding cuts across the strike of the ore body at acute angles. Traditionally the ore body has been divided into a northern and southern part based on the location of the central shaft, which lies on section line 5400N. Despite this the orebody is essentially continuous.

The southern ore zone is around 180m long and consists of a composite vein of quartz and mineralised country rock dipping about 60° to 70° to the east. The northern orebody consists of the continuation of the west lode and of the east and central lodes, which are less distinct toward the south. The latter reef lodes consist of more massive laminated smokey quartz with phyllite partings. Milky white quartz is also present, but is generally barren.

The northern ore zone has been mapped at 20 - 40m width near the surface and widens substantially at depth. At around 100 – 120m relative level (“mRL”) (the underground 4 and 5 Levels) horizontal widths exceed 100m. The dips are generally near vertical at surface, but the eastern boundary flattens moderately at depth to less than 65° around 150mRL. The lodes merge approximately 400 - 500m north of the central shaft. Further to the north the orebody narrows and continues as one near-vertical reef 15 - 25m in width.

The length of the main historic underground mining zone extends to 1,800m while the total strike length of the Bibiani mineralised trend is around 4,000m. The mineralisation remains open at depth.

Mineralisation is related to emplacement of quartz veins, which occur as either sheared, stockwork veins with quartz-ferroan dolomite, or as larger, up to 20m wide, locally stylolitic quartz reefs. Both veins types are associated with pyrite +/- arsenopyrite. Fine-grained disseminated Fe-carbonate and sericite alteration with pyrite +/-arsenopyrite occurs adjacent to the veining.

Mining Methods

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Comminution

Crushers and Mills

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Processing

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Production

Commodity	Units	2024	2023
Gold	oz	....
Gold Equivalent	oz		....

Operational metrics

Metrics	2024	2023
Annual ore mining rate	....
Annual processing capacity	....	....
Ore tonnes mined	....	....
Tonnes processed	....	....

Personnel

Job Title	Name	Profile	Ref. Date
.......................	.......................		Sep 7, 2023
.......................	.......................		Sep 7, 2023
.......................	.......................		Sep 7, 2023
.......................	.......................		Sep 8, 2023
.......................	.......................		Sep 7, 2023
.......................	.......................		Sep 7, 2023

Total Workforce	Year
......	2019