Christina is also from Canada and she has such a fascinating background. She is trained in archaeology and she is able to identify shells and things like that. When I look at a shell, that's what I see - a shell. She looks at a shell and she sees a star shell or a pipi, a venus shell, a triangle shell, a cockle, scallop shell, some mussel shells (which way back then people used to eat with and sharpen and used as knives) (okay, I knew this was a mussel shell) and even an ostrich foot shell.
Bianca dug up this shell (that I honestly thought was a pretty ugly shell and it looked all broken, but Bianca liked it when we saw it) and Christina immediately said that it consisted of 3 shells stuck to each other. Of course now I am able to see it, but not before.
Here is an ostrich foot shell: