Copper specks on clad coinage

JimW

I was looking at some BU 1999-D 50C and noticed that some of them seem to have sporadic small copper colored specks on some of them.
Is this due to a weak clad layer or some of other part of the minting process, or something post-mint?
They've been in unopened paper-wrapped rolls for the last 22 years....
TIA!

JBK

Without photos it is just idle speculation.

MsMorrisine

photos both sides, full shots and closeups