An artificial eye made of glass for people who have lost an eye in an accident or through surgery. Glass eyes are not spheres. The only one I've ever seen was more like the shape of a cupped hand. While they can be made out of actual glass, they are commonly made of acrylic. To get the prosthetic eye to match an existing eye, an artist will carefuly paint the iris, pupil and even some veins. Usually the muscles in the eye socket are arranged to allow some movement of the glass eye. This gives the appearence of a lazy eye rather than a totally fake one. The glass eye is not worn at all times, and getting one in can be rather difficult at first.

My father had his eye removed after getting a rare form of cancer. Besides getting used to inserting, removing and taking care of the prosthesis, he also had to get used to only having one functional eye.