pebbles

With coastal erosion and the warming climate, he said the beach and nearby properties were at risk without the protective pebbles in place.

He said he had many moments over a two-week excavation where he thought he had discovered something, only for experts to tell him he had a knack for finding "shiny pebbles".

The post added: "The shell had been dug out of the pebbles by someone apparently, before someone else called 999 as they realised what it was."

“And from there ... it’s like pebbles down a mountain.”

Fill a small area with colorful potting mix, smooth pebbles and little shovels or spoons that are safe for them.