The black economic empowerment (BEE) group is paying ZAR 1.6bn ($151m) for the stake.
The investment, along with an earlier issue of 96m new shares that raised ZAR 2.4bn, will be used to fund capital infrastructure projects.
The Brimstone led investment was welcomed by Grindrod chief executive, Alan Olivier, who said he was “looking forward to their valuable input.”
Brimstone has a 59% share in the BEE consortium, Calulo Investments Pty 20%, Solethu Investments Pty 13%, Safika Holdings Pty 5% and Adopt-A-School Foundation 3%.
Calulo,
