The hollow cavities, or chambers, of this specimen give it an undeniable artsy feel. This is a robust fossil, weighing in at over 12 pounds, yet at once also delicate and serene. Polished on all sides, custom stand included. Ammonites were predatory mollusks that resembled a squid with a shell. These cephalopods had eyes, tentacles, and spiral shells. They are more closely related to a living octopus, though the shells resemble that of a nautilus.