When the whale first excretes it, it is pale white and very soft. It does indeed have an excrement smell to it like it came from the intestines .
After a time floating about in the ocean Ambergris actually hardens, changes its smell, and becomes smooth, firm lumps that are dark brown outside, grey or pale yellow inside. Eventually, Ambergris washes up on beaches. Most pieces found are just a few ounces, but anecdotally, pieces up to a few hundred pounds have been known.
It breaks apart easily, and has a somewhat earthy, sweet aroma. Older pieces will smell somewhat musty.
Ambergris used to be used in perfumes, and is still used in scenting the anointing oil that is used in the Coronation ceremonies for the British monarchy.
It was popular in English cooking in the 1600s. Very old recipes may refer to it as “ambergreece”, and call for a small quantity of it to flavour a frosting or a posset.
Ambergris melts at 144 F / 62 C; vaporises at 212 F / 100 C.
The word “Ambergris” comes from the name of two colours, amber and gris (gris being “grey” in French.)