JOHANNESBURG (miningweekly.com) – JSE-listed diamond miner Thabex subsidiary Angel Diamonds has submitted an application for a mining lease at the Kolo kimberlite project to the mining commissioner of Lesotho.

The mining lease application included a prefeasibility investigation with the view of establishing a diamond mining operation, with a planned minimum through-put capacity of 5 t/h, using a dense medium separator (DMS) recovery plant, Thabex said in a statement, on Monday.

Angel processed a total of 5 088 t of the Kolo kimberlite, producing 388 ct at a grade of 7,73 ct for every 100 t, using a 20 t/h DMS recovery plant with a bottom cut-off screen size of 2 mm.

Thabex stated that Angel Diamonds had exported 332 cs to South Africa for analysis at $135/ct. The company estimated an inferred resource of about 2,7-million tons, at an average grade of 208 710 ct, from surface to a depth of 100 m.

In October, Thabex announced that it would sell a 42% stake in Angel Diamonds to Mantle Diamonds for $2-million.

Mantle, a private diamond exploration and development company which plans to list on the Aim-market, would also have the option to acquire the balance of Thabex’s interest (28%) in Angel Diamonds at market value, after a feasibility study has been completed and a mining right has been granted.

Mantle has completed a core-drilling programme during the last quarter of 2008, and has commissioned a 10 t/h DMS recovery plant with a bottom cut-off screen size of 1 mm including a Flowsort X-ray final recovery section.

The main aim of Mantle’s present sampling programme was to recover a minimum parcel of about 1 500 ct of diamonds in order to assess the economic viability of the Kolo kimberlite pipe.

Thabex stated that all diamonds recovered to date have not been independently valued and a value would only be reported once an independent valuation has been compiled or the diamonds produced during prospecting have been sold.

Meanwhile Angel has also prospected five other kimberlitic occurances on the prospecting license area, including the Sekameng kimberlite pipe. Core drilling of this occurance will start during the second quarter of 2009.

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