It has now bought just under 10mln shares for around £7.7mln, a move that chairman Haresh Kanabar previously called "expedient".
The last purchase of shares from IMIC was hailed by the City, potentially saving the company US$10mln in its overall takeover of Afferro.
IMIC has tabled a 120p a share bid for Afferro, which consists of 80p in cash and a convertible loan note worth a further 40p. It is now waiting on the relevant regulatory approvals for the acquisition.
IMIC's US$200mln takeover of Afferro will be transformational for the latter's flagship project, the 2.5bn tonne Nkout iron ore deposit in Cameroon.
The plan is to create the infrastructure required (namely rail and port) to get ore from the mine to the leading export markets of the world.
The key to this is its partnership with African Iron Ore Group, led by Afren founder Bert Cooper. African Iron Ore has high-level political contacts in West Africa as well as close links with the Chinese.
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