I don't really do much involving Bakelite [I'm more into military metal-cased radios] but a while back I re-worked a WWII-era "Microphone, Hand No.8" - see here -
https://www.vintage-radio.net/forum/...ad.php?t=99220
that had gone a bit whitish on the surface.
"Solvol Autosol" and a bit of vigorous rubbing removed the discolouration.