What effect will LED lights have if they shine on T206s?

[Snowman]

Originally Posted by Cliff Bowman

I need to put my comic collection in a greenhouse for six months then.

You would need to remove them from any slabs for it to work. It's a result of the photosynthesis process. It deoxidizes the paper as the plants convert carbon dioxide into oxygen. Then as the oxygen releases and combines with the uv light from the sun, it reverses the toning of papers which was caused by oxidation due to the acidity of the paper stock. That's also why cards from specific sets tone more than others. The heavier the wood pulp content is in a card stock, the more acidic it will be, and the more it will tone over time.