VANCOUVER - Goldcorp Inc. (TSX:G) is making a $2.6-billion takeover play for Montreal-based Osisko Mining Corp. (TSX:OSK), which has an operating mine in northern Quebec and other projects in Ontario.

Vancouver-based Goldcorp, which rivals Barrick Gold (TSX:ABX) in size, is offering a combination of stock and cash that values Osisko at C$5.95 per share — about 15 per cent Friday's closing price.

Osisko hasn't commented publicly on whether its board supports the takeover offer, which is being made directly to Osisko shareholders.

Goldcorp. is one of the Canada's largest gold producers and says the acquisition of Osisko would provide it with a major mine in Quebec and other assets with growth potential.

In addition to the Canadian Malarctic gold mining complex in Quebec's Abitibi gold belt, Osisko owns the Hammond Reef gold project near Thunder Bay, Ont., and land holdings near Kirkland Lake, Ont.

Under Goldcorp's offer, Osisko shareholders will be entitled to receive 0.146 of a Goldcorp common share plus C$2.26 in cash for share.

Goldcorp shares closed Friday at $25.29 at the Toronto Stock Exchange, giving the company a market value of about $20.5 billion. By comparison, Barrick's market value was $23 billion as of Friday.

Osisko's market value before the Osisko offer was about $2.3 billion, based on the Jan. 10 closing price of $5.17 per share.

Goldcorp says its offer allows Osisko's shareholders to sell their shares at about 20 per cent above the 20-day average in return for some cash and an equity stake in the larger mining company.

"From a financial and strategic perspective, this offer represents a compelling transaction that is consistent with our strategy of improving the overall quality of our portfolio," said Chuck Jeannes, Goldcorp's president and chief executive officer.

"We are particularly pleased to be making a further substantial investment in the Province of Québec, one of the best mining jurisdictions in the world."

Goldcorp's own Eleonore project in northern Quebec is due to begin production later this year and the acquisition of Osisko would provide an opportunity to leverage "corporate and regional synergies."

Synergies typically refer to either reduced overhead, sometimes involving staffing reductions, and greater growth opportunities by combining the resources of two businesses.