Ceresin is a widely used ingredient in cosmetics, personal care, and skincare formulations. Depending on its function, it may serve as a moisturizer, preservative, emulsifier, or active ingredient to enhance the overall effectiveness and performance of a product.
Ceresin (also cerin, cerasin, cerosin, ceresin wax or ceresine) is a wax derived from ozokerite by a purifying process.

The purifying process of the ozokerite commonly comprises a treatment with heat and sulfuric acid, but other processes are also in use.
Uses include:
- An alternative to beeswax in ointments
- (Historic) laboratory-supply bottles for small amounts of hydrofluoric acid, which were made of ceresin wax; this was before polyethylene became commonplace.