Description of Bug: Applying a padded lining to a copper display case turns the display case tin. It still correctly shows as "copper" when examined, but has the sprite for a tin display case.
Reproduction Steps:

1.  Have a copper display case.
2.  Attempt to craft a padding for the case.
3.  Case changes sprite to the incorrect metal color upon successful craft.

Error message (if applicable): N/A
Screenshots: