The things in the middle looked like seashells to me. They could also be the links of a chain. Hence the name of this piece.
The large size is at the preceding link.
Today's Gratitude Item: My dad. As in, he took some of my fractal greeting cards to work and managed to sell sixteen of them to his workmates! My dad is a generally amazing human being and I was really grateful that he was prepared to take my "stuff" into his office and sell it.