The gold torc now being examined by the National Museum was one of two similar artefacts discovered last week on a beach in Co Mayo, The Irish Times has learned.
It is understood a Cork businessman with family connections in Mayo was walking on a beach last week as the tide was ebbing and saw something glistening. When he investigated, he found two gold torcs possibly more than 3,000 years old.
The pieces of jewellery, one approximately 31/2 inches in diameter, the other marginally smaller, were slightly tainted but otherwise in remarkably good condition. The businessman returned to Cork with one of the torcs and left the other one in Mayo.
In Cork he asked a local jeweller to examine it and the National Museum was called. An official of the museum has gone to Mayo and it is understood that an archaeological investigation of the beach where the torcs were found is under way.
The businessman has asked that his identity be kept secret.
Details of the location of the find are being withheld by the National Museum.
Under the National Monuments (Amendment) Act 1994 such finds automatically become the property of the State and the onus is on the finder to report anything of value which is discovered.
The Act makes provision for a reward to be paid both to the finder of a valuable object and to the landowner on whose land it is discovered, but does not make it a requirement that any reward be paid.
Yesterday, Mr Eamonn Kelly, keeper of Irish antiquities at the National Museum, explained that where a bona fide discovery has been made the inclination in the museum has been to reward the finder.
However, where an object of historical value is illegally discovered, i.e. with a metal detector, the museum is likely to take a different view.
Mr Kelly said it was relatively easy to determine, once experts have been called in, if an illegal dig had been made at a site on which a metal detector was used.
Discovering such ancient objects might not automatically make the finder a rich man, Mr Kelly said.
In fact, if major recent discoveries were anything to go by the rewards were often small.
After the discovery of the Derrynaflan hoard in Co Tipperary in 1990, the finder and the land-owner received just £25,000 each, although the objects recovered included a silver chalice and paten with gold and amber inlay, a bronze ladle and bronze basin.