Under Australian Law Ambergris is considered to be a Whale product, and as whacky as it may sound, collecting, keeping, selling etc is governed by a whole raft of rules and regulations of our glorious nanny state. Apparently it is used in many of the high-end perfumes of the world, and is sought after by well-paying perfume manufacturers. Occasionally you see news stories of huge lumps of it that somebody has found on a beach somewhere in the world, go for hundreds of thousands of dollars. A quick google search finds prices mentioned ranging from US$50,000 per kilo upwards.
Until a few years ago it was a mystery to the scientific world, until someone realized that for centuries people had been dabbing perfumes on their faces made from Whale vomit. Once it was realized that the best stuff was from Sperm Whales it became highly regulated. You know how it goes, Licenses, Fees, Regulations and Prohibitions etc.