Manufacturers use many different grades of enamels to coat the Magnet Wire, this is for thermal and flame retardant reasons mainly.
A red coating usually indicates a higher resistance to heat and flame...
That's ineresting. Do you know what is used for enamel?
Or what would take it off... Seeing as how sulfuric acid doesn't.
It's strange that even after chopping it up (which one would suppose exposes a raw surface)
it does not react.
The wire in harddrives is Usually of an orange color.