Gold Tissue Paper Gold Trim On Fine Bone China Plates?

Gold Trim on Fine Bone China Plates? - gold tissue paper

I had an English bone china tea during storage for a few years. It was wrapped in tissue paper, acid-free boxes and stored at room temperature. I grabbed it today and realized that the gold border has deteriorated in some places. Some of that was a little black, and others who have lost their luster and uneven. Could have been me, I am worried about the effects of moisture and oxidation.

How can I return it without damaging it?