Degradation of Objects Indoors

All examples mentioned above demonstrate that even glasses that have never or rarely been in contact with liquid water can suffer from deterioration. Above a certain limit in relative humidity, the glass surface attracts water molecules that form a film on the surface and are ready to initiate ion-exchange reactions. 

Apart from chemical degradation, there are examples of glasses in museums with signs of damage connected to their former use. Many of those examples are damaged by scratches that provide prominent spots for further corrosion. 

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