The 500 pound World War Two device was picked up during dredging work.
Titanic Memorial Services 100 Years On
Memorial services have taken place to mark exactly 100 years since the Titanic sank on her maiden voyage from Southampton.
Rev Huw Mosford held a short service on the MS Balmoral to remember the 1,512 people killed, after the vessel reached the fateful spot in the Atlantic overnight.
Deckboys then threw wreaths into the water from three sections of the cruise ship, which has been retracing the route of the ill-fated liner.
The 1,309 passengers of the ship - including descendants of the victims - heard the captain make an announcement before an emotional minute's silence was held for the victims of the accident.
It was 2.20am on April 15, 1912, when the liner sank on its maiden voyage.
It was sailing from Southampton to New York when it collided with an iceberg 375 miles off Newfoundland. Of the 2,228 passengers on board, only 706 survived.
In Southampton overnight, flares were let off in Andrews Park, where a full-scale outline of the ship's been laid out on the ground.
Today a special service is taking place at St. Mary's church in the city.
549 people from Southampton - most of them crew - died when the ship hit the iceberg.
640 men were killed when the South African troop carrier was hit by a cargo ship in 1917.
The 79-year-old man suffered a serious head injury in the Cranmer Road car park in Winton.
Two Girls Indecently Assaulted Last Sunday
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