London-listed Rainbow Rare Earths’ Gakara project, in Burundi, has produced and exported its first 25 t batch of high-grade rare earth concentrate.

The commissioning of the gravity processing plant at the mine, which started production in December 2017, has also been completed.

Gakara produced 279 t of concentrate in the quarter ended March 31, following the 75 t produced in December.

Production levels are expected to increase steadily over the rest of this year, as mining and processing methodologies are tested and optimised.

The average grade of concentrate produced was 62% total rare earth oxide. The grades were consistent at between 61% and 64% in the quarter under review.

 All run-of-mine (RoM) ore processed during the quarter was sourced from the Gasagwe pit.

 Rainbow is developing “highly attractive” additional sources of RoM ore within the Gakara mining licence area in order to reach its target run rate of 5 000 t/y by the end of this year.

 These areas are now expected to be in operation ahead of Gashirwe, the originally planned second mining area, owing to their vein prospectivity and speed of development.

 The company experienced relatively high production costs of $2 068/t of concentrate, but expects costs to reduce significantly as production rates increase and the element of fixed costs is spread over larger tonnages.

Rainbow reports that rare earth oxide prices strengthened “considerably” during the quarter after dipping towards the end of 2017, with Rainbow’s basket increasing 11% from $12 270/t as at December 31, 2017, to $13 570/ t as at March 31.