Oak moss Absolute,(Evernia prunastri and furfuracea) is a tree moss used as a fixative base note in perfumery. A fixative holds the blend together and allows the aroma to unfold in layers of transformational scent. A natural perfume is always about transforming and uplifting energy to its highest form. Diluted in a perfume, Oak moss is very calming. I use it in my Sea breeze perfume base combination, which is very lightly scented. Oak moss has low volatility and evaporates slowly without affecting the evaporation of other essential oils in a blend. It blends well with many other essences, used in small amounts, and other fixatives, such as Benzoin, Labdanum, Vetiver, Patchouli, Tarragon and Lavender Concrete.