It was a catchy tagline from a catalog some years ago. And true.
Shark are all cartilage and attitude. And, as one might discover on a foggy January wander along a beach – teeth.
Having no tooth-fairy to look after them, these teeth sink to the bottom of the sea.
Once the chompers hit mud or sand, chemistry does its magic.
Minerals from the mud (or sand) shimmy into the teeth, making the once-pearly whites, dear, into something rich and chestnut-colored, or black.
Or, according to the lore, blue.
Which makes sense, because sharks have been swimming about for millions of years. And some grow up to 35,000 teeth in a lifetime.
I suppose someone has done the math, but it’s a lot of teeth underfoot. One might say, the opposite of hen's teeth, even.