The Lubambe copper deposit is one of approximately 30 copper/cobalt deposits occurring within the Central African Copperbelt. It is located at the north-western extremity of the Zambian portion of the Copperbelt. The deposit is hosted within sediments that accumulated in an intracratonic rift, which was subsequently closed during the Lufi lian Orogeny. The deposit mineralisation is defined as the ore shale (OS) type of mineralisation. Copper mineralisation is largely hosted within the OS1 Member, whose true thickness varies from 3 to 14 metres. The lower-most 1.5 metres of the OS1 Member contains very little copper, due to leaching which preferentially occurs at the base of the OS1 where the contact between the siltstone and conglomerate/arkose represents a permeability channelway. The transition to greater than 1% total copper (TCu) is abrupt and takes place over centimetres, above a thin red iron oxide-rich marker layer, which probably acted as a redox boundary. The upper contact of the greater than 1% total copper zone (assay hanging wall) is also well-defined in the assay profile, but is not as sharp as the assay footwall contact.

Mineralisation occurs as finely disseminated sulphides along bedding planes and cleavage, in thin veinlets, and in lenticles and stringers, comprising of chalcocite, chalcopyrite, bornite, digenite, covellite, pyrite and carrollite. A large proportion of the nonsulphide copper minerals occur along fractures and veins and consist of ma ........

Lubambe is an underground operation utilising the Longitudinal Room and Pillar mining method.

The current mining method employed is a variant of room and pillar ‘modified room and pillar’ which also falls under open stoping methods (unsupported underground mining methods).This method has stope designs of 20-25 m with 6m rib pillars and 5m sill pillars that are not designed to hole.

The mining sequence of modified room and pillar is as follows:
- the excavation is mined to completion for ore development with primary support installed;
- thereafter secondary support is installed;
- production drilling commences, and
- lastly stoping is conducted.

The firing sequence used has the following sequence:
- Ring 1 is fired;
- Rings 2 and 3 are taken together;
- Ring 4 to the last ring in the panel are fired in a mass blast.

This firing sequence is adopted for the whole mine but subject to change upon geotechnical recommendation if there are ground condition issues in the area.

Lubambe Studying Alternative Mining Method
The current mining method of Longhole retreat stoping in the flatter dipping (<40) areas is not entirely appropriate, due to in the high dilution that it attracts and the low dip angle affecting ore recovery. The proposed mining method Inclined Room and Pillar (IRP) for these flatter areas is more selective and would target a higher production grade by reducing waste diluti ........

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