Objects made of glass served to imitate perishable, organic materials. The material properties and, in particular, the many diverse colours and shapes it can assume, make glass the ideal base material for artificial eyes. For aesthetic reasons, glass eyes were used for living people who had lost an eye as well as for stuffed animals in natural history collections to make them look alive. Glass eyes can also be found inserted into wax portraits or dolls. In particular during the nineteenth century, organic collectables such as plants and animals were no longer made of wax, but of glass.