![The colour palette of the glass artist: sample frames with around 800 colour nuances.](https://blog.nationalmuseum.ch/app/uploads/musterrahmen-mit-rund-800-farbnuancen-300x225.jpg)
Colours revealed by light
Painted glass windows have been bringing light and colour into dark church rooms since the 13th century. But how is a glass painting actually made?
![The oldest surviving medieval glass painting in Switzerland: Mary with Child, around 1200, St.Jakobskapelle, Flums SG.](https://blog.nationalmuseum.ch/app/uploads/maria-mit-kind-dig-59573-in-35-136x300.jpg)
Glass puzzle
![Knife & special scissors for the templates.](https://blog.nationalmuseum.ch/app/uploads/messer-und-spezialschere-fur-die-schablonen-dig-55313-ch-insitu-300x225.jpg)
![The glass painter at work on the details.](https://blog.nationalmuseum.ch/app/uploads/der-glasmaler-bei-der-arbeit-an-den-details-dig-55293-ch-insitu-300x225.jpg)
![The actual colour of a glass only becomes visible after it has been fired. These fired colour samples are used for comparison with the template.](https://blog.nationalmuseum.ch/app/uploads/farbmuster-nach-dem-brennen-dig-60235-lm-177262-300x206.jpg)
![The various work steps at a glance.](https://blog.nationalmuseum.ch/app/uploads/die-verschiedenen-arbeitsschritte-auf-einen-blick-dig-55297-ch-insitu-300x182.jpg)
Painted glass windows have been bringing light and colour into dark church rooms since the 13th century. But how is a glass painting actually made?