Caledonia Mining is planning to extend the depth of the central shaft at the Blanket mine in Zimbabwe by an additional 250m down to 1,330m.

Currently under construction, the shaft was initially scheduled to be in production during the fourth quarter of next year. However, it is now expected to be fully commissioned by the end of the first quarter of 2020.

Under the proposed extension plan, two further production levels on 34 (1,110m) and 38 (1,230m)  will be added, in addition to the already planned 26 (870m) and 30 (990m) levels.

Caledonia Mining CEO Steve Curtis said: “We are very pleased that the long track-record of sustained resource growth at Blanket, particularly the continued discovery of resources at depth with good grade continuity, supports an extension of the central shaft project at Blanket.

“We are now in a position to continue investing for the future.”

“The Central Shaft is already a transformational project for our business, and to extend the project an additional 250m in depth including development on 34 and 38 levels will potentially secure Blanket’s operating future for the next 20 years taking exploration potential into account.

“Based on the strong geological indications of resource and grade continuity at depth, which was supported by our recent resource update, the excellent progress in the current shaft sinking, and most importantly the strong cash generation from Blanket’s current operations, we are now in a position to continue investing for the future.”

The extension and associated capital development of additional production levels are estimated to cost around $18m.

Based on a preliminary economic assessment (PEA), the project has a net present value (NPV) of $193m over the mine-life.

The company expects total production from measured and indicated resources to be around 420,000oz over the life of mine. Production from inferred resources is anticipated to be in the range of 550,000oz-600,000oz between next year and 2031.