Marubeni of Japan and Hong Kong-listed Winsway Coking Coal Holdings Ltd. had paid $1 billion for the mine in 2012 when coal prices were booming.
Winsway said it has decided to reduce its dependence on coal and to diversify into services for other bulk commodities.
"Although these efforts have not yet resulted in significant earnings, the company is confident that the proposed new business model will enable it to better utilize its logistics resources and contribute to its earnings in the near future," Winsway said in a statement.
Marubeni also confirmed the deal in a statement Wednesday, but did not offer an explanation for the sale.
Up Energy said Marubeni will receive $1 for its 40 per cent stake, while Winsway will get $1 for 42.74 per cent of Grande Cache and retain a 17.26 per cent interest.
Marubeni, one of the largest Japanese trading houses, will also have the right to buy back a 15.78 per cent interest under certain conditions, while Winsway may buy back up to 16.86 per cent.
Grande Cache is a producer of metallurgical coal and holds coal leases covering more than 22,000 hectares in the Smoky River coalfield in west-central Alberta.
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