Aluminum Alloy Revolver frame

[Hondo44]

Looks like finish degradation, not wear. Looking closely at your photo, it appears like more of the finish is headed in that direction. Your only practical solution is to see if the factory will redo the finish under warranty.

 

[idsubgun]

I can't tell from your photo if the affected area is into the parent metal or not. But the only way for anodizing to fail is for the parent metal to fail as well. Anodizing isn't a coating like paint. Anodizing goes 50% into the parent metal and 50% on top. To strip anodizing you must also strip the 50% parent metal. For this reason it's never a good idea to simply strip anodize unless you take everything on the part into question. If a hole is tight tolerance, the hole will probably be too big after stripping. Same for threads. After stripping the treads will be loose.
BTW, the proper way to strip anodize is the reverse process of applying it.
If the area has sat against your body, I'm sure sweat has eaten through the anodize into the aluminum. At this point the only thing you can do is paint it (i.e. Duracoat, etc) if it bothers you.

 

[bykerhd]

You can polish it off but then you will have a shiny area that will not match the rest of the gun.
It won't hurt anything to leave it.

 

[tbobcar]

The best anodize stripping is an electrolytic process, you are probably not set up for it.
In fact I strongly suggest you don't
try a wet DIY method.
If the shooter were mine I'd get a metal finisher to do it, polishing is an art-form. Yet again I suggest you have a professional do all the refinishing, if you do it you might be very unhappy with the results.
Also, chemicals are dangerous, have a pro do the work!