Tietto Minerals at 1-year high on Zhaojin's sweetened $733m bid

China's Zhaojin Mining said on Monday it is raising its offer to buy the shares it does not already own in Tietto Minerals to up to A$733-million, sending the Australian gold explorer's shares to a one-year high. Last October, Zhaojin had placed a bid for Tietto Minerals, which owns its flagship Abujar gold mine in Côte d'Ivoire, for about A$629-million.