Vancouver-based Rockwell Diamonds has recovered an “exceptional” 189,6ct gemstone diamond from its Klipdam mine, in South Africa's Northern Cape province, the company announced on Thursday.

The gem, which is being analysed and valued, is oval in shape, slightly flattened and strongly resorbed, and shows features typical of top-colour, high-value type-two gemstones, Rockwell said in a statement.

“Initial indications suggest that the diamond is D Colour with the potential of a very high recovery polished product.

“Besides sparse black inclusions on the one side of the rough diamond, the heart of the stone appears to be clean and could result in a final polished diamond of considerable value,” the company said.

Rockwell, which is the subject of an unsolicited takeover bid from global investment company Pala Investment Holdings, also reported that it has found a “small but rare” 1,13ct intense blue flawless diamond, also from the Klipdam operation.

The firm is still considering its options for marketing the stone, which has been submitted for appraisal and valuation.

Klipdam has produced rare fancy stones in the past, including a 7,28ct intense flawless pink stone, which was sold in November 2007 for $145 000/ct.

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