Gibbs plating issue, What happened?

I've had two gives for several months and the last few it's been put away after a good cleaning and drying . After every shave a rinse them with hot water and dry it ( and all my razors) with a microfiber cloth. This one is been stored in a little leather travel case, one of the ones with the flap that folds over, and in a dry dresser drawer. You'll see in the pictures both ends of the riser ( not sure what the exact term is for this piece) but one was down to the brass practically and the other chrome is severely cracked. Now this razor was in excellent condition and very nice chrome all over, from when I bought off eBay. This is not from use it was perfect chrome or at least appeared to be when I bought it and the last time I put it up. I used a polishing cloth and got the pepper sized crumbs off it. So the middle picture is the other side and it's severely cracked where it was perfect plating. Has somebody sprayed it with chrome or something, because this razor is like 1950s model? So what's really going on and how can I fix this inexpensively?