But the silence on the part of the world's biggest aluminium maker has done little to dampen the enthusiasm here for an old-fashioned takeover battle among resource companies, once the toast of Australian investors but lately pushed aside by "new economy" stocks. Other heavy hitters in mining, including The Broken Hill Pty Co Ltd, Rio Tinto Plc and Billiton Plc have been shortlisted as potential suitors too, although less so exclusively for the alumina operations.

Alcoa and WMC are 60/40 partners in Alcoa World Alumina and Chemicals (AWAC), which accounts for a big slice of Australia's nearly A$1 billion (US$610 million) a year alumina industry. Alumina is refined from bauxite to make aluminium. Alcoa is believed to hold pre-emptive rights to WMC's interest in AWAC, regarded as a plum in the aluminium industry for its capability to refine 7.3 million tonnes annually.

WMC shares catapulted 4.5 per cent in early Thursday trading to a high of A$7.13, buoyed by a A$385 million share buyback to acquire up to five percent of its own shares, providing more fodder for speculators who read the buyback as defensive. And why not? The share registry of the diversified miner is wide open. Also, despite Thursday's jump, WMC's shares remain well below January's recent peak. A weak Australian dollar is just more icing on the cake for the U.S. dollar-wielding Alcoa.

WMC chief executive Hugh Morgan insists the buyback represents WMC's focus on growth and value building for shareholders while reducing debt as part of an ongoing capital management programme. With a current market capitalisation of A$8 billion and with a premium yet to be included, a takeover will be the largest in Australian history, beating last week's A$8 billion merger of Commonwealth Bank of Australia Ltd and Colonial Ltd.

Using WMC's A$9 a share high touched at the start of 2000 as a benchmark, the company as a whole would be worth more than A$10 billion. Fresh from clinching a US$4.3 billion merger with the US rival Reynolds Metals Co, Alcoa has done its part to fuel the rumours too. Last week it surprised local market watchers by announcing it intends to list on the Australian Stock Exchange. Three days later it bid A$1.60 a share for Eastern Aluminium Ltd while shareholders were still pondering a lower offer from Greece's Elval.

Eastern's main asset is a 10 percent stake in the Portland smelter west of Melbourne which is operated and 45 percent owned by Alcoa. Alcoa also owns outright the smaller Point Henry smelter closer to Melbourne. WMC, formerly called Western Mining to mark its mining activities in Western Australia, over time has reinvented itself as a diversified resource house drawing revenues from gold, nickel, copper, uranium, fertiliser and alumina.

Analysts doubt Alcoa has much interest in running assets outside aluminium, so if it was serious about getting its hands on all of AWAC, it could look to negotiate an amicable divorce from WMC via a premium to shareholders for AWAC. With AWAC firmly in its pocket, Alcoa could march onto th ASX as Australia's only pure integrated aluminium investment. This designation is currently enjoyed by Comalco Ltd, but will change if Rio Tinto succeeds in its stated takeover of Comalco, as analysts expect.