Crinoids are marine animals, related to the starfish, sea urchins and sea cucumbers that lived at the bottom of the Great Lakes when the dinosaurs roamed. They had a long stalk with a mouth at the top and it's the pieces of the stem, defined by a round disc shape with a hole (or filled in hole) in the middle, that are commonly found on our beaches.
This piece by Lora Richardson is truly a work of art. Adorned with a variety of very small crinoids, it's certainly a conversation piece. And just think -- you'll be wearing a piece of history!
Note: Each piece is unique and will differ somewhat from this photograph.