All I've ever managed to find was a bunch of sea shells:

They call it a beachcomber’s dream, but the chances of finding it, are slim to none. This is why a recent find at Streaky Bay of the rare substance ambergris, which is essentially sperm whale vomit, is a coup for a South Australian fishing family.
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The South Australian West Coast ambergris weighs around 14.75 kilograms.

Mr Jury says that SA Director of Fisheries Will Zacharin has quoted his estimate of the price of ambergris at approximately US$20-a-gram.

The stuff's used in perfumes, and it has a really appetising "manufacturing" process. And to think we make fun of how loud Olivia burps...