A woman walking on the beach at Maryport found was is believed to be a lump of solidified palm oil.
Tests are now being carried out to find out what it is.
Allerdale Borough Council said it's the first incident it has come across involving the discovery of solidified palm oil on the beach.
The council want to reassure the public that this is an isolated incident and yesterdays discovery will be disposed of safely.
If the public spot something they believe is palm oil, they are advised to keep dogs away from it and report it to the customers services team at Allerdale Borough Council on 01900 702800.
More top news
It is the start of summer - but feels more like autumn. Will we see the sunshine return? Ross has your regional forecast here:
The scheme will offer existing employees of the Council’s Education Service the chance to study locally while still being employed.
North Cumbria University Hospitals NHS Trust says action is being taken to address fire safety concerns at the Cumberland Infirmary.