South Africa's BlueRock Diamonds PLC (LON:BRD) sold 71% more carats from its Kareevlei mine last year as the opening up of a new section led to a strong improvement in average grades.
Just over 5,800 carats were sold in 2018, with 189,990 tonnes processed from total tonnage of 572,664 tonnes mined from the Kimberley-based kimberlite.
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The average grade increased 34% to 3.28 carats per hundred tons (cpht), up from 2.45 cpht last time, with the average stone size recovered during 2018 around 0.35 carats in size and more than 90% of diamonds of gem or near gem quality.
As the AIM-listed company moved its mining focus from the KV2 area of Kareevlei to KV1, the second half of the year saw a more consistent and higher grade, which BlueRock said has continued into 2019.
Revenue increased to £1.4mln from £0.95mln, with a loss before tax of £2.4mln as operations continue to move towards the economies of scale required to become profitable, as well as a swing to a £0.6mln foreign exchange loss versus a gain the prior year.
Also in 2019, the company began 365-day operations in March, leading to a +30% increase in operating time, and has strengthened its management team for the mine.
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Two stones were recovered and sold during the first quarter of 2019, as well as a 24.98 carat diamond in June, the largest diamond to date, which sold for $190,000
A recent £982,000 fundraise to support expansion plans for the Kareevlei mine is expected to lead to the business being self-funding in the future.