JOHANNESBURG (miningweekly.com) – Aim-listed BlueRock Diamonds’ Kareevlei mine, in the Kimberley region of South Africa’s Northern Cape province, processed 38 781 t of ore in the quarter ended March 31, compared with the 9 310 t processed in the first quarter of 2017.

This production represents 14.1% of the company’s production target for this year.

Grade increased to 3.8 carats per hundred tonnes (cpht), compared with 2.45 cpht in the prior comparable period.

Further, BlueRock sold 1 563 ct of diamonds in the first quarter of this year, which represents 16.5% of the lower end of the company’s guidance for this year.

“The results were consistent with seasonal expectations as first-quarter production will always be hampered by the extended Christmas and New Year break, coupled with the Northern Cape rainy season experienced in the first quarter of each year,” BlueRock stated.

The company added that the average price of $378/ct, compared with the average price of $362/ct achieved in the prior comparable period, reinforces the company’s position as one of the top ten highest value per carat diamond mines in the world, while reflecting the high quality of diamonds recovered at Kareevlei.

Meanwhile, BlueRock plans to start mining the K1 area at Kareevlei in the second half of April.

Initially, the top calcretised level will be removed and it is expected that BlueRock will be mining kimberlite in May for processing in June.  

K1 has an inferred grade of 6.3 cpht, compared with that of K2 of 4.5 cpht. The company expects that, over time, this will lead to an increase in Kareevlei’s overall grade.

K2 will continue to be mined as K1 is developed and bulk sampling is continued on K5, giving the flexibility to ensure consistent supply of good-quality kimberlite to the processing plant.

The emphasis remains on maximising the value of Kareevlei and, accordingly, BlueRock has decided not to pursue the Jubilee project that had previously been announced and have thus let the option lapse on this project, given that the results of initial testing suggested a low-grade mine. 

This follows after BlueRock entered into an agreement with Koedonza Olives to mine the 1.5 ha Jubilee kimberlite pipe, in the Windsorton area, 40 km north of Kimberley.

The company received a bulk sample of about 2 500 t to ascertain the likely grade and quality of any diamonds coming from Jubilee, which turned out to be economically unviable.