The deal, which has approval from both companies’ boards, will see James River acquire about 13.8 million tons of proven and probable reserves and mining permits from Cheyenne.
Cheyenne is selling about 10.2Mt of surface reserves and 3.6Mt of underground reserves in the transaction.
Production from the new Cheyenne mines is expected to reach a rate of 500,000t per annum by the end of the year.
James River expects about 90% of the production will be high-quality utility steam coal.