Bruce, I have had sterling silver wire discolor from the initial application of aqua fortis but it was always only temporary. Once I rubbed out the rifle the silver always returned bright. I have had the silver darken on me due to use, but again, oiling and rubbing out the stock or waxing it brightened up the silver. Same thing with a silver inlay in ta rifle barrel. Turns dark from the rust browning process but shines right up during carding.
DMR
