Ambergris is a grey to black, waxy mass that forms in the digestive tract of whales. Individual stones of ambergris can be found either in the sea or on the coast. This valuable substance is also used in perfume making as a base note for many fragrance compositions. Ambergrease is also considered a good compound as it slows down the evaporation of pleasant smelling substances. The fragrance is described as pleasantly woody, dry and a little tobacco.