I had one back in the late 80's and I remember it said it was supposed to be Nickel finished but it was some sort of satin (almost matt) silver paint finish (not Nickel coloured as Nickel coated handguns at the time sort of had a gold/brass tinge to them), it was very hard wearing and in the end I actually spent ages removing the coating with wet and dry paper to reveal the alloy underneath, I then polished it up and fitted black rubber Hogue grips.
Pete