The amended offer will now be open for acceptance until December 3, 2008.
The expiry date could be further extended if conditions of the amended offer are not satisfied or waived.
Mineralogy has also indicated it is amending its offer to include all of Waratah's outstanding common shares, rather than just shares held by Mineralogy and any of its affiliates.
However, Mineralogy is continuing to offer $C1.41 per share.
Brisbane-based Waratah said the offer from Mineralogy was “inadequate” and did not compensate shareholders “for the size, quality and strategic value of Waratah’s assets”
The formal notice of the extension and offer variation has already been filed with Canadian securities regulatory authorities.
However, Waratah said the board of directors and special committee of the company as well as its financial and legal advisors had not had the opportunity to review the full terms and details of the amended offer.
Waratah said it intended to formally respond to the amended offer once the review of the formal notice of extension and variation is completed, but will continue to recommend shareholders reject Mineralogy's offer dated October 3, 2008 and not tender shares to it.
Waratah insists more attractive value alternatives to the current takeover are being aggressively pursued by the board and shareholders should hold out for a better deal.
Shares in Waratah were up 15c to $C1.20 at close of trade on the TSX yesterday.