So good news and bad news.
Good news. It is not chromed. WHY the PO stripped it of the blueing and left it bare I have no idea.
Bad news. It has pitting and rust from severe neglect. The internals also had gummed up lube everywhere, but par for the course at this point.
The discoloring you see on the frame, slide and barrel is not gsr as far as I can tell... appears to be wear to the metal itself.
After afew passes with some CLP I managed to get the action buttery smooth and feel very nice, but there is some things that won't be fixable until it gets blasted and coated. The magazine had some odd debris inside of it hindering the follower, and the follower had what looked like paint? on it... Cleaned most of it up and the feeding improved, but the spring does feel fairly weak compared to a normal spring.
That said I went and grabbed a holster today along with some JHPs. CONFIRMED CZ75B mags DO fit and work. In fact the 75B mags are a PERFECT fit... the included mag has some slop, but the 75B is flush with zero slack.
At this point I'm debating to have it blasted and reblued, or just cerakote it. I like the way blueing looks, but never been a fan of the way it wears.