Conservation and restoration of stained glass

Stained glass conservation refers to the protection and preservation of historic stained glass for present and future generations. It involves any and all actions devoted to the prevention, mitigation, or reversal of the processes of deterioration that affect such glassworks and subsequently inhibit individuals' ability to access and appreciate them, as part of the world's collective cultural heritage.

Source: Wikipedia — Conservation and restoration of stained glass (CC BY-SA 4.0)