Ambergris
For centuries people desired the substance ambergris. It is commonly known for its horrible odor. However, over time it starts to become rather sweet. For hundreds of years, this material has been included in expensive perfumes. Some say you can even eat it.
Whale By-Product
Ambergis originates in the bile ducts of whales and then goes out. This process is a bit gross. It is very rare so it is worth a ton. Lucky for Steven and Viola, they just stumbled upon it. They started to get excited.