It was initially thought a time-expired flare had been found at Birling Carrs, near Warkworth, on Wednesday, May 19.
Howick Coastguard Rescue Team and their colleagues from Amble were paged by Humber Coastguard to deal with it.
However, on closer inspection it became apparent it was not a flare due to its shape and size.
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Photographs were taken and sent to Humber Coastguard for them to send to Explosive Ordnance Disposal (EOD) for their expert opinion.
They made the decision to send a disposal team from Catterick in North Yorkshire.
Howick Coastguard Rescue Team, posting on Facebook, said: “An inspection was made and the device, believed to be a military projectile, was confirmed as safe.
“The first informant did exactly the right thing in calling 999 and asking for the Coastguard, and we would urge anybody who finds any suspicious looking object on our coastline to do the same.”