How can I treat and restore discolored artwork?
Q. Dear Donia,
A. Dear Marna,
What a wonderful find! I would not advise any bleaching of artwork at home. Common household bleach will destroy the artwork over time. It may look bright and lovely when you do it but it will crumble to dust. The best option is to take them to a paper conservator for treatment. There are several options for reducing this sort of staining and a trained paper conservator will be able to find the right course of treatment.
You can find a conservator in your area by referring to the American Institute for Conservation's "Find a Conservator" (Find a Conservator) page.
When framing, be sure to find someone who can do conservation framing, meaning using museum-quality matboard to mat and mount the object and using UV blocking glass or Plexiglas. For more advice on framing, speak with your conservator as they will have other recommendations based on treatment.