[1] The rare earth elements are hosted in a system of narrow veins in the northeast-trending Kibaran Fold Belt consisting predominantly of bastnäsite with secondary monazite.

[2] The Gakara deposit has a high percentage of magnet rare earths such as neodymium and praseodymium, used in motors, generators, wind turbines, and electric vehicles.

In April 2015 Rainbows International Resources, a wholly-owned subsidiary registered in the British Virgin Islands, was granted a rare earth exploitation permit, with a 25-year mining agreement.

[5][a] The license covers about 39 square kilometres (15 sq mi) The base camp is in the village of Matambu, Commune of Gasenyi.

[1] The processing plant was built in 2018 near the town of Kabezi about 15 kilometres (9.3 mi) south of Bujumbura between Lake Tanganyika to the west and the RN3 road to the east.

[4] Thyssenkrupp Materials Trading made a 10-year distribution and offtake agreement with Rainbow for up to 10,000 tonnes of rare earth concentrate, starting in January 2018.

[2] Extracting rare earths from concentrate is a complex process which uses a lot of energy, and the waste can cause environmental problems.

[7] A July 2019 report by SRK Consulting addressed concerns about pricing of rare earth mineral concentrate.

[4] In April 2021 the Ministry of Hydraulics, Energy and Mines notified Rainbow Rare Earths that permission to export concentrate had been temporarily suspended.

Gakara was fully written down, with net assets impaired to nil, in Rainbow Rare Earth's accounts for the year to 30 June 2023.