The deal will be equivalent to the price paid to BHP Billiton in 2013 for its interests, Dominion said.
Dominion Diamond chairman and CEO Robert A Gannicott said: "Although the sale by Chuck Fipke of his interest in the Ekati Project ends his financial involvement with Canada’s first diamond mine, his contribution to its discovery and success goes well beyond that."
Ekati mine comprises the Core Zone, which includes the operating mine and other permitted kimberlite pipes, and the Buffer Zone, which hosts kimberlite pipes with development and exploration potential.
Fipke’s 10% interest in the Core Zone will be sold for $50m and the base purchase price would be payable in installments over 31 months.
The company will sell its interest in the Buffer Zone for $17m, which would be payable in cash on closing.
The transaction is expected to be completed in September this year.
