The newly constructed diamond recovery plant is “a lot gentler on the diamonds", provides the "least diamond breakage", and cuts water consumption by 30%.

The plant was opened by Northern Cape Premier Dipuo Peters, De Beers chairperson Nicky Oppenheimer and De Beers Consolidated Mines (DBCM) CEO David Noko.

The treatment plant is one of the investments made by De Beers at Finsch to improve diamond recovery efficiency.

“Importantly, it improves the value of diamonds recovered by liberating diamonds from their host rock in a ‘diamond friendly process’,” the company said in a media release.

The new plant includes the installation of high-pressure roll crushers to replace outdated rod milling.

The plant has capacity to treat 7,2-million tons of kimberlite a year and is enabling Finsch to produce at a rate of 2,2-million diamond carats a year.

The efficiency improvements have been achieved with the addition of a coarse dense medium separation (DMS) plant and by converting the existing DMS plant to a fines DMS plant.

The upgraded process will ensure that correctly prepared diamond-bearing kimberlite is fed into a new final recovery plant that includes the latest x-ray diamond recovery technology.

De Beers technology research and manufacturing division DebTech installed much of the technology at Finsch.

A new thickener and associated infrastructure has improved internal water recoveries, reducing water consumption from 0,6 m3 per ton treated to 0,4 m3.

Finsch mine, which employs 2 226 people, is itself technologically advanced and has an automated driverless horizontal truck-haulage system in its underground workings.

DBCM has invested R3-billion in South Africa in the past four years.

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