Another radioactive particle has been recovered from the public beach at Sandside near the Dounreay nuclear plant in Caithness.
Radioactive particles have been traced in the sea and the shore
It is the 67th hotspot to have washed ashore from the nearby UK Atomic Energy Authority site.
The metallic fragments of reprocessed reactor fuel are linked to a rogue historic discharge from the plant.
The particle, found on the west side of the beach, has been taken back to a laboratory at Dounreay for analysis.
The particles have been discovered on the seabed and beaches near Dounreay over the past two decades.
Last week, the Scottish Environment Protection Agency (Sepa) said it had submitted reports to the procurator fiscal over the finds.
UKAEA declined to comment on the threat of legal proceedings.