Well gunney, it sounds to me like you have a late 80's vintage Gov't Model MKIV Series 80 in stainless steel. The sides of the slide and frame were polished up nice and the top of the slide, bottom of the front part of the slide and some parts of the frame had a rough texture like it was sandblasted. It would give the appearance of the gray finish you mentioned. The gun was probably fitted with black Goodyear rubber.
If it were me, I'd leave it alone. I happen to like the look.
However it is your gun, and if you can't live with it, you can certainly polish the texture out using any number of methods. One of the benefits of a Stainless gun, is being able to polish to your desired finish. I think you can even send it back to Colt and for a fee they will polish it all the way to the Ultimate Bright finish.
gunny, as'WS23' said above, that's the way they came, one to reduce the 'glare' off the top of the slide and the bottom,front and back of grip frame so as to not show as many handling marks, if it was 'shiny' you'd spend everyday polishing out the handling marks.
I too like them like the way they came............... /forums/images/graemlins/wink.gif
The matte finish on the slide top cuts down the glare which can be a problem with open sights in bright sunlight. It doesn't bother me in fact I used to have a grip mounted red dot scope on this one but at one point had a smith replace it with this Docter sight and do a trigger/action job on it. When I got it home I saw the grayish slide top and thought maybe he had scratched the slide and refinished the top to hide his goof. I was angry until I saw other examples just like it. The point is it's apparently not so noticeable after you get used to it.