The company produced 4,362 carats from own operations and 4,800 carats from royalty mining contractors.

Revenues from diamond sales were increased 15% to $8.8m and total carat sales were up 34% to 6,677 carats.

First quarter volumes of gravel processed at the company’s three producing mines increased 26% to 1.13 million m3.

Rockwell’s Middle Orange River (MOR) operations at Saxendrift Mine reported 19% rise in volume production, and average grade improved 59% to 0.62 carats per 100 m3.

Rockwell Diamonds president and CEO James Campbell said: "These results are underpinned by our increasingly diversified production profile in the MOR where we now have three producing MOR mines, all of which have multiple mining faces."

"We saw a progressive improvement in production as a result of sticking to our MOR-focused strategy during the first quarter," Campbell said.

"Contributing to this milestone was the improving performance at Niewejaarskraal where we mined according to the new mine plan and completed the production ramp up."