Stones with Holes - how did they get there?

The photos of the stones in my "Corner View" post from last week (By the Sea) received some interesting comments that got me thinking...

Francesca said, " We also find some of those pebbles with holes on our beaches, I wonder what the story is."

I had already been wondering about how the holes occured...the stones are flint and I thought there must be a  "vein" of softer material within the stone, which dissolves or erodes more quickly than the rest of the stone as it it tossed around in the ocean. Or perhaps there was a small fossil within the stone that has long since disappeared? The stones were found on part of the Jurassic coast of Devon so I guessed this must be the most likely theory.

It turns out I was right about the fossils... flint is a kind of compressed sedimentary rock, and as it was being formed all those thousands of years ago, small pieces of marine plants, sponges and little creatures became fossilized within the flint. After a time, the sea breaks up the flint and the fossils inside get washed away leaving a hole.

Now to investigate Kerstin's comment about the "Chicken Gods"!