New York (CNN Business) Starbucks is testing out a new cup. It's hoping you won't notice.

On Monday, the coffee chain started trialing a new recyclable and compostable cup in some locations in New York, San Fancisco, Seattle, London and Vancouver. The new version of the cup is still made from paper, and should look and feel the same as a traditional Starbucks cup. But inside, the vessel is coated with a compostable liner, rather than the plastic one used in Starbucks' regular paper cups. That means the new cup can be composted in industrial composters, unlike the cups Starbucks uses today.

"Customers will not see any noticeable difference from the current cup," the company said in a statement discussing the test.

The new liner should make it easier to recycle Starbucks cups.

Starbucks has been trying for decades to reduce waste by developing a greener cup. It's a hard problem to solve: Plastic-lined paper cups are light, stackable and effectively keep liquid from seeping out. And technically, at least, they are recyclable.

But it's difficult to do so because many recycling facilities don't separate paper cups from their plastic linings. If the cups end up in recycling facilities that don't separate the materials, they could gum up machines and harm the equipment.

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