MELBOURNE (Dow Jones)--Aston Resources Pty. Ltd. is in talks with two Chinese groups interested in taking a cornerstone stake in its Maules Creek development and securing coal offtake from the mine, a person familiar with the situation said Wednesday. The Brisbane-based vehicle of mining investor Nathan Tinkler is planning an initial public offering of up to A$500 million and another person familiar with the float said a prospectus could be ready within weeks. Tinkler, who completed the purchase of Maules Creek from Rio Tinto Ltd. (RTP) subsidiary Coal & Allied Industries Ltd. (CNA.AU) for US$480 million in February, has said he is looking to list 15%-20% of the company. Tinkler has said that the mine is expected to produce about half thermal coal, used in power generation, and half semi-soft coking coal used in steelmaking. It isn't clear whether the Chinese groups Aston is talking with are power generators or steelmakers. -By Alex Wilson, Dow Jones Newswires: 613-9292-2094; [email protected] (END) Dow Jones Newswires July 07, 2010 03:10 ET (07:10 GMT)