UPDATE 1-Osisko Gold to buy metals portfolio from Orion Mine for C$1.13 bln

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June 5 (Reuters) - Canada's Osisko Gold Royalties Ltd said on Monday it had agreed to buy a precious metals portfolio from U.S. private equity firm Orion Mine Finance Group for C$1.13 billion ($839.40 million) to expand its diamond, gold and silver asset base.

Osisko will pay Orion C$675 million in cash and the remaining C$450 million in Osisko shares.

The portfolio consists of 74 royalties, streams and precious metals offtakes and will result in Osisko holding a total of 131 royalties and streams, the company said.

As a part of the deal, Osisko will be entitled to some production from the Renard diamond mine in Quebec, Brucejack gold and silver mine in British Columbia and the Mantos Blancos mine in Chile.

Reuters had reported in January that Orion Mine was in talks to either sell or publicly list the portfolio.

Maxit Capital LP, BMO Capital Markets, National Bank Financial and PricewaterhouseCoopers were Osisko's financial advisers.

Orion's financial advisers were CIBC World Markets Inc and Haywood Securities Inc. ($1 = C$1.35) (Reporting by Yashaswini Swamynathan in Bengaluru; Editing by Shounak Dasgupta)