The nautilus joins the ranks of cephalopods like the squid, cuttlefish, and octopus. However, the nautilus is the only one with a chambered shell. Interestingly, this shell is a natural logarithmic spiral.
Joining land and sea, mollusk and mineral, cuttlefish bone casting is a method of metalworking that produces one-of-a-kind pieces. Cuttlefish are cephalopods with a unique internal structure called a cuttlebone, which is light, porous and easy to carve. Smiths have been using them as molds for casting small objects, usually in silver, for hundreds of years. (Here’s a brief overview of the technique)
One of the coolest things about cuttlefish bone casting is that the molten metal takes on organically-shaped ridges from the structure of the cuttlebone. Many artists use these as a design element, evoking their origins in the sea. Each mold can only be used once, so each cast object is unique. Australian artist Katrina Newman uses the technique to create pieces that fuse ancient and modern, craggy and sleek, as in this striking pendant called Post by the Sea.