Since colored contacts are being worn by a considerable number of people nowadays a lot of companies are offering services to tint already existing lenses owned by customers. However, there are many ways of coloring lenses. Opaque mickey mouse contact lenses are used to completely alter the natural color of the eye. This feature cannot be added on to a clear pair of lenses already constructed. However, if the customer wants to tint his or her existing pair of lenses then this can be done. The latter type of coloring is known as enhancement coloring which is mainly used to modify the natural eye color by brightening or darkening it.