This Old Fossil's Petrified Brachiopod

Been tied up all day dealing with Homestead, Mother and family business and have hardly stepped outside the back door.

I've photographed a fossil that I found ages ago amongst some ballast with which we dressed the outside of my propagating house. I used to sit on the ground and play with the stones with my grandson when he was a toddler. We loved looking for pretty, unusual, colourful or smooth ones. I've always liked stones, we had a tumbler when my children were young that turned ordinary gravel into beautifully smooth gems.

I've tried to identify my fossil. I think it could be a Terebratulina (made me think of Bradgelina) brachiopod. The camera has had a strange effect. The fossil is in the form of an indentation but in my pic it looks to be the opposite. I've included a Swan Vesta for scale.