Ten days ago, Canadian gold miner Alamos Gold publicly made an offer to buy rival miner Aurizon Mines (UNKNOWN:AZK.DL2) for C$4.73 a share, a 40% premium over Aurizon's then-current price. This morning, Aurizon gave its response: Not enough.

In a unanimous decision, Aurizon says, its board of directors has voted to reject Alamos' offer -- or, more specifically, to recommend that its shareholders reject the offer. Aurizon is going one step further, and has voted to adopt a "shareholder rights plan," more commonly known as a "poison pill," which aims to make a takeover by Alamos without the board's approval prohibitively expensive.

In a statement, Aurizon took pains to argue that its shareholder rights plan is in fact "not intended to prevent a takeover of Aurizon or to secure continuance in office of management or the directors," but rather to "provide the Board with adequate time to identify, develop and negotiate value-enhancing alternatives, if appropriate, to any unsolicited take-over bid, including the Alamos Offer and to encourage equal treatment of shareholders in connection with any take-over bid offer." The board termed Alamos' offer "financially inadequate and opportunistic."