Pictured above is a sword lined with shark teeth, a helmet made from the skin of a puffer fish and a trident sharpened with shark teeth. The people of the Gilbert Islands in the Pacific Ocean have been making them since European first contact in the Eighteenth Century. They're objects of fascination to archaeologists, but also to zoologists because they're often made from sharks that don't live in the area:
But the biggest surprise was that some of the teeth belonged to two species—the dusky and spottail sharks—which no longer exist near the Gilberts!
Back then, they were common enough that their teeth were among the most popular choices for weaponsmiths. Today, no one has seen them within several thousand kilometres of the islands. Even before scientists knew that they were there… they weren’t any more.