Chairman George Jones said the board considered that the terms of the offer did not provide adequate value or certainty to Sundance shareholders.
Mr Jones said: "At the same time, Sundance will continue to progress its advanced negotiations with potential strategic partners in respect to possible joint-venture, financing and offtake arrangements to develop its Mbalam iron ore project in the Republics of Cameroon and Congo.
"The company has the vision, passion and technical expertise to develop the Mbalam Project, which will produce 35 million tonnes per annum of high-grade hematite."
SDL Price at posting:
49.0¢ Sentiment: Buy Disclosure: Held