Indian Metals and Ferro Alloys (IMFA) has acquired a 70% stake in a Indonesian coal mine, through its subsidiary Indmet Mining, for $8.7m.

IMFA Group chief financial officer Prem Khandelwal said that the total quantum of reserves in the coal mine is difficult to ascertain since a detailed assessment is yet to be done.

"Currently, drilling operations are on at the site. We will be able to get an idea of the amount of reserves after it is complete," Khandelwal said.

IMFA group will finalise the investment required for the operations, based on the outcome of a study on the infrastructure required to be set up in the area.

The coal extracted from the mine will be used to take up merchant sales in and around Indonesia.