[Imbuing] Why can't we alter old items?

[Heimi]

I'm trying to alter old HCI/DCI shields that the Stratics guide says are alterable..but its not letting me. Why is this?

 

[Basara]

Have they been enhanced with colored metals (or wood, if a wooden shield)?

Imbuing won't work on items enhanced or crafted out of the colored materials prior to the release of SA.