

Some are literally metal. See: Chrysomallon squamiferum: a deep-sea extremophile mollusk that lives on volcanic vents in the Indian Ocean. They have a shell made of iron sulphide and aragonite. Their lower body also has an armor coat of sclerites (fancy word for “hardened body part of invertebrates”, like pieces of an exoskeleton) made of mineralized iron, giving them their colloquial name “Scaly-Foot Snail”
Please stop falling for the culture war stuff and pay attention to the bigger picture.