BlueRock Diamonds PLC (LON:BRD) has taken its first samples from the K5 pipe at the Kareevlei diamond mine in Kimberley, South Africa.
While too small a sample to make firm conclusions, Adam Waugh, chief executive, said the results were encouraging and warranted further exploration.
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“Although K5 is smaller than K1, K2 and K3, early indications suggest a similar grade to K2.
“However, the average size of diamonds mined was much larger than those of K2."
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K5 is undeveloped and not included among the Kareevlei’s inferred resources.
A limited bulk sample of 7,500 tonnes of kimberlite was taken from 5m to 10m below ground level and processed in December.
Elsewhere, production from the K2 pipe has recommenced after Christmas following amendments to the crushing circuit.
Waugh said: "We have used the time afforded to us by the Christmas break to make further improvements to our crushing circuit in order to increase throughput to the processing plant.”
Bluerock is shifting to quarterly reporting and repeated that it produced 2,110 carats in the three months to November with revenue of US$374 per carat on average.