The bone, believed to be a tibia, was found offshore at Belongil Seashore in Byron Bay about 1.30pm on Saturday, Might 6.
After the invention, police divers have been despatched to the location and carried out a search of the seaside.
"The bone has undergone preliminary forensic examination, which decided it was human," NSW Police stated.
Police stated a forensic investigation is underway to find out who it belonged to.
The testing may also examine it to identified lacking individuals.
The investigation is continuous.
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