The making of prosthetic eyes from cryolite glass.

Glass eyes were once widely made in the UK and were the standard ocular prosthesis. Most are now made from PMMA (poly methyl methacrylate) also known as acrylic glass. Modern glass eyes are made from cryolite glass that is highly biocompatible and does not include any chemical additives.

Despite the dominance of PMMA in modern prosthetics, there are some that argue that glass eyes are better for some patients and that glass eyes reflect light in a way that is more similar to the natural eye.  In some European countries, such as Germany, glass is still the normal standard for ocular prosthesis whereas in the UK they have largely been replaced by synthetic materials.

Cryolite is a specialised white glass which becomes translucent at high temperatures. It has been specially developed for artificial eyes and is produced by specialised glassworks. The coloured parts of the eye prosthesis are also made of glass. Iris markings, pupil, veins etc. are melted onto the cryolite glass with the aid of coloured glass.

The base material for the manufacture of artificial eyes is a tube of white cryolite glass, from which a sphere is blown. The iris is built up from coloured glass, a black pupil is added and the cornea reproduced.

• Glass has been replaced by synthetic materials – however, there is still a demand for glass eyes some consider them superior to synthetic eyes for their more realistic appearance and because they are less likely dry out.
• Lack of skills to make glass eyes – the ocularist who has reintroduced glass eye making to the UK had to go to Latvia to find the skills.

• Valdis Valters making a glass eye on YouTube
• Daily Mail article on Jost Haas, Maddy Fletcher, Dec 2022
• The Glass Eye Maker – Jost Haas (Documentary)
• The last of the glass eye makers, BBC March 2012