Legendary cone-shelled snail, long spoken of as "the world's most precious seashell."
Worth a literal king's ransom throughout the late Renaissance and Baroque era, even as recently as the late Sixties, specimens were sold for the equivalent of $70K in today's money -- and for good reason, for its "glories" are many.
The impression of being an artifact is so strong, it's uncanny: the shell itself is generally four to six inches long, yet it's covered in a non-repeating pattern strongly resembling a Chinese painting of an infinite mountain range. Each specimen is unique: the pigment varies from sepia-like to golden, it might have tortoise-shell colored and patterned bands in the design, and no two patterns are alike. Up until very recently, it was a mystery where the actual animal lived: approximately near the Philippines and/or Indonesia, it is an inhabitant of deep, sandy bottoms, much deeper than most fishermen's nets would (then) go. Catching one was only the beginning, since the smaller end is armed with a deadly needle-shaped poison barb. And to crown the intrigue and mystery, the pattern is identical to Stephen Wolfram's Rule 30, thus putting its geekoid status through the roof.
Not long after Specimen 100 was auctioned, in 1969, its breeding grounds were found -- and its range was found to be far more extensive than previously known. It's a good thing they're neurotoxic, or we'd be eating them to near-extinction as a gourmet treat.
Now you can buy a specimen for less than $100. Still lovely.