Mylar flips are OK, but they need to be stored in archival quality pages.
Cheap PVC pages are a NO - NO. Although the reaction takes place very slowly, (10 years or more), eventually bronze and copper ancients will darken to black, as the plasticiser in the PVC pages gasses out, and can get to the coins, through the Mylar of the 2 x 2's.
Look for the best quality clear pages from 'Lighthouse' or similar.
Cheap PVC pages are a NO - NO. Although the reaction takes place very slowly, (10 years or more), eventually bronze and copper ancients will darken to black, as the plasticiser in the PVC pages gasses out, and can get to the coins, through the Mylar of the 2 x 2's.
Look for the best quality clear pages from 'Lighthouse' or similar.




















