Glencore puts Cobar, Lomas Bayas copper mines on the block

Glencore is selling a few of their copper mines

Miner and commodities trader Glencore has hoisted the for-sale sign over two copper mines - Cobar in Australia and Lomas Bayas in Chile - after being approached by buyers.

In a statement, the company said it had received "a number of unsolicited expressions of interest for these mines from various potential buyers," adding that a buyer could snap up one or both of the mines.

Glencore said that it would issue an update on deal talks only if a sale was agreed.

The company had previously flagged asset sales, after concerns over its debt pile and a rout in commodity markets led to the stock tanking last month. The cost of protecting against default on Glencore debt also rose sharply.

As a result, Glencore undertook to reduce its debt by about $10 billion from the $30 billion it reported in late June, and has already offloaded a small Brazilian nickel project.

Read MoreGlencore scrambles on asset sales, debt concerns

The sale of the company's metal-byproducts business at two mines in Peru was one of the sales being eyed, people familiar with the transaction said earlier this month.

Also high on the company's to-do list is a partial sale of its agricultural business, a deal Glencore's management hoped would net multiple billions of dollars, a person familiar with the matter told CNBC earlier this month. That transaction, which would ideally involve one or more sovereign wealth funds buying between 20 and 30 percent of the grains unit, was in the works but unlikely to close until early next year, this person added.

Glencore said last Friday it would also cut 500,000 tonnes of global zinc production, around one third of its annual zinc output, due to low prices.

"Glencore is announcing today a 500,000 tonne reduction of contained zinc metal mine production across its operations in Australia, South America and Kazakhstan," the company, which is the world's biggest zinc miner, said in a Friday release to the Hong Kong Stock Exchange.

Glencore said operations at Lady Loretta in Australia and Iscaycruz in Peru would be suspended, while George Fisher and McArthur River in Australia and various mines in Kazakhstan will cut production levels.

—Reuters contributed to this report.