(Adds details on possible suitors, context, background)
By Clara Denina and Nicole Mordant
LONDON/VANCOUVER, May 3 (Reuters) - Mining-trading group Glencore Plc has hired the Bank of Nova Scotia to sell a portfolio of royalty assets, including one for the Antamina copper-zinc mine in Peru, four people familiar with the process have told Reuters.
The Antamina mine royalty makes up the bulk of the value of the package and could fetch up to $250 million, the sources said. The portfolio includes several much smaller royalties from other mines and exploration assets owned by Glencore around the world, they added.
It is not clear whether Glencore will sell 100 percent of the royalties, which gives the owner the right to receive a percentage of production from a mining operation, or retain a stake in them.
There is no certainty the process will result in a deal, the sources said. The people, whom Reuters spoke to over a period of several days, declined to be named as the talks were confidential.
Glencore declined to comment. Bank of Nova Scotia did not have an immediate comment.
The London-listed miner owns and operates nickel, zinc, copper and coal mines around the world and also owns royalties on several operations.
Glencore is looking to maximize the value of its assets as it moves from cost-cutting to pursuing growth. Following the commodities crash of 2015 and early 2016, the company sold off assets to cut debt after its earnings and shares were pummeled by a commodities downturn.
Potential buyers of the royalty portfolio could include mining royalty and streaming companies such as Canada-based Franco-Nevada Corp and Silver Wheaton Corp, the sources said. Streaming, like royalties, is a type of alternative finance for the mining sector.
Franco-Nevada is interested in looking at any royalty being offered, its chief executive officer, David Harquail, said. "It is only a question of price," Harquail said in an emailed response to a question from Reuters.
Silver Wheaton declined to comment.
Glencore owns a 33.75 percent stake in Antamina and has monetized a portion of the mine's output. In November 2015, it agreed to sell future silver output from Antamina, a by-product of the mine, to Silver Wheaton for $900 million in cash to reduce debt. Franco-Nevada bought a $500 million precious metals stream from Glencore last year.
Glencore's partners in Antamina are Anglo-Australian miner BHP Billiton Plc with a 33.75 percent stake, Canadian miner Teck Resources Ltd, with 22.5 percent and Japan's Mitsubishi Corp with 10 percent. (Reporting by Clara Denina in London and Nicole Mordant in Vancouver; Additional reporting by John Tilak in Toronto and Barbara Lewis in London; Editing by Denny Thomas, Bill Rigby and Jeffrey Benkoe)