It was found by a staff member in a shopping basket at around 4pm.
A police spokesperson said: “We were called to the Asda store in Memorial Avenue at just after 4pm today (Thursday 5 June 2014) to a report of a ‘bullet’ being found in a shopping basket.
“Officers attended the scene and recovered a small metal object, removing it from the store. It will now be subjected to testing to establish what it is.”
“If you have any information call police on 101 quoting incident 596 of 5 June 2014, or call Crimestoppers anonymously on 0800 555 111.”