While no companies have yet been named, ZYL said proposals had ranged from $US46.4-$72.2 million with varying commercial terms and conditions.
The company said it was targeting the domestic market but believed opportunities to achieve a higher sale price may exist in a speciality export market.
ZYL chief executive Ian Benning said the interest reflected positive results from a study that confirmed the site could yield 580,000 saleable tonnes per annum of coal over a 12-year mine life.
“We are pleased with the level of interest received and the competitive nature of the proposals,” he said.
“That the proposals have been received on the back of the Mbila interim feasibility study results highlights the robust economics and strategic significance of the project.”
Mbila is situated in South Africa’s KwaZulu-Natal province, has a JORC-compliant resource of 125 million tonnes, and is scheduled to start production in 2013.
The tenement’s sister project Kangwane is located in the country’s Mpumalanga province and contains a JORC-compliant resource of 136.3Mt.