Running discussion on SP, page-62653

From the annual report:

AVZ now owns 75% of the joint venture company, Dathcom Mining SA, following completion of both Agreements.* The remaining 25% of Dathcom Mining is owned by La Congolaise d’Exploitation Minière SA (Cominiere), of the DRC Government over which AVZhasapreemptiverighttopurchasefurtherprojectequity.

Does anyone know:

1. How much of that 25% AVZ has the right to acquire?, and
2. Is the purchase by negotiation, or at some set $figure / formula?