The Yaramoko gold mine is situated in the Houndé greenstone belt region in the Province of Balé in southwestern Burkina Faso. The property is located approximately 200 kilometres southwest from the capital city of Ouagadougou.
The Yaramoko gold mine consists of two gold deposits: the 55 Zone, a fully underground mine which is currently in production, and Bagassi South, which is currently in development.
The 55 Zone mine went from its initial discovery in 2011 to production in five years and was completed early and under-budget. Production began in May 2016 and Commercial Production was declared in October 2016.
The 55 Zone is an operating 750 tonne-per-day underground operation which utilizes longhole stoping with cemented rock fill as its primary mining method. The 55 Zone mine has proven and probable ore reserves to a depth of 750 metres of 1.8 million tonnes grading 11.47 g/t gold for 662,000 ounces. Roxgold has been increasing inferred resources at depth at the 55 Zone and plans to infill drill these resources to enable conversion to reserves.
Bagassi South is the second high-grade underground gold mine on the Yaramoko property and is currently in development. Bagassi South consists of two gold deposits: QV1 Zone and QV’ (QV Prime) Zone.
The Company is currently advancing the development and construction of the QV1 Zone, which is the main deposit of the Bagassi South project. The deposit is geologically similar to the 55 Zone and is located approximately 1.8 kilometres south of the 55 Zone which is currently being mined.
The Bagassi South QV1 deposit feasibility study confirmed robust economics for a potential 350-tonne-per-day underground mine. Bagassi South contains probable mineral reserves of 458,000 tonnes grading 11.54 g/t gold and is expected to increase the Yaramoko Gold Mine gold production by an estimated average gold production of 40,000 ounces per year to 2023. Bagassi South mine operations would benefit from shared infrastructure, management and support services already in place for the 55 Zone mine. First ore is expected in late 2018.
To support the additional 350 tonne-per-day additional throughput expected from Bagassi South, the existing Yaramoko gold mine process plant will undergo an expansion increasing throughput from 750 tonnes-per-day to 1,100 tonnes-per-day.
The north-northeast-trending Boni shear zone divides the Yaramoko Gold Project between the predominantly Houndé volcanic and volcaniclastic rock to the west and the Diébougou granitoid domain composed predominantly of granitic rock with minor volcanic rock to the east. The main lithological units are mafic volcanic rocks, felsic intrusions, and late dolerite dikes. This region is considered prospective for orogenic gold deposits, which typically exhibit a strong relationship with regional arrays of major shear zones.
The largest granitic intrusion found on the Yaramoko concession is host to both the 55 Zone and Bagassi South Zone gold deposits. Both deposits are set on the eastern margin of the intrusive in the footwall of the Yaramoko shear along conjugated dextral faults located in extensional position to the regional shear zone. The bulk of the gold mineralization occurs in dilatational segments of the shear zones where quartz veins are thicker and exhibit greater continuity.
The Bagassi South Zone deposit is located 1.8 kilometres south of 55 Zone and the surface definition of the veins can be traced over a strike length of some 800 metres and dips to the northeast. Gold typically occurs as coarse free grain in quartz and is associated with pyrite.
The Yaramoko property consists of a large regional land package of approximately 230 km2, located on the Hounde Belt. The majority of known anomalies and deposits are located along the Boni Shear regional break and the second order Yaramoko Shear. The high grade deposits of 55 Zone and Bagassi South are located in the footwall of the Yaramoko Shear along East-West extensional zones, which are unique extensional style high grade deposits.
The majority of the Yaramoko concession is largely unexplored. Regional Drilling programs are currently in place with a focus on with drilling along the Boni Shear, Haho, Kaho and Houko with approximately 64,000 metres of drilling planned for 2018.