Aim-listed Tertiary Minerals has announced additional laboratory analytical results from the recent Phase 4 drill programme at the Discovery zone in Target A1, at its Mushima North project in Zambia.

The results follow the company's news release of the first laboratory assay results on September 1 and are from a further seven drill holes.

All seven holes intersected near surface, silver/copper/zinc mineralisation and extend the mineralisation at depth with the majority of holes ending in mineralisation.

Mushima North is located in the prospective iron/oxide/copper/gold region of Zambia.

Target A1 is a polymetallic, silver/copper/zinc prospect, where the company has previously reported a near-surface exploration target of 15-million to 30-million tonnes at 40 g/t to 60 g/t silver-equivalent, and which is located 28 km to the east of the historic Kalengwa copper/silver mine, which is currently under redevelopment.

Tertiary MD Richard Belcher says results from the infill drilling continue to increase the company’s confidence on the extent and continuation of grade within the exploration target at the Discovery zone, with intersections including 82 m at 53 g/t silver-equivalent (0.88% copper-equivalent) from only 7 m below surface.

The higher-grade zone is further supported with the new results and includes an intersection of 22 m at 105 g/t silver equivalent (1.75% copper equivalent) from 64 m.

"Moreover, the majority of the holes reported here end in grade indicating the mineralisation remains open with depth and pushes the known depth of mineralisation beyond the envelope of the previously defined exploration target. The full depth extent and the possibility for the current oxide mineralisation to transition to sulphide mineralisation are yet to be tested.

"Additional laboratory results are expected over the coming weeks and we look forward to updating our shareholders in due course,” says Belcher.

A total of 39 reverse circulation drill holes were drilled as part of the Phase 4 drill programme. For the drilling at the Discovery zone, holes were collared along a series of east-west drill lines spaced about 100 m apart (north-south) and 50 m apart along the east-west lines and drilled to vertical depths of up to 128 m.

This was the maximum depth capability of the drill rig under the drilling conditions, in particular the higher-than-expected water table and resultant wet samples.

Drilling was completed in two passes to allow the updating of the company's geological model as new data became available and to enable the programme to be more dynamic.

The company says additional laboratory results are expected over the coming weeks.