Aspiring Perth-based copper and gold miner Tethyan Copper Co Ltd is under a renewed hostile takeover threat from Hong Kong-based Crosby Capital Group. Crosby?s bidding vehicle, Skafell Pty Ltd, has lifted its offer 21 per cent to 77.5 cents a share, making its bid worth $102.6 million. The offer was made after the Australian share market closed with last trades in Tethyan at the new offer price. The initial 64 cents a share offer attracted acceptances of less than 2 per cent and was unanimously rejected by the directors of Tethyan, which controls the Reko Diq copper/gold project in Pakistan, rated as among the world?s top 25 copper deposits. Skafell said its new offer allowed Tethyan shareholders to avoid the ?significant risk? associated with Reko Diq. Earlier this month, Tethyan said further drilling had doubled the total mineral resource at Reko Diq to more than 2.4 billion tonnes containing 27 billion pounds of copper and 21 million ounces of gold. Tethyan is proposing to develop the project in joint venture with London-listed copper mining company Antofagasta Plc, which will inject an initial $177 million into Tethyan in return for half the project and 17.3 per cent of Tethyan itself. Skafell said that under the Antofagasta deal, Tethyan shareholders faced significant dilution without indication as to any increased value created through the dilution.