How to clean reddish purple-ish silver clad

[ilovemycows]

I'm a newbie. Just sorted out all the silver clad from the copper clad and shook it in a jar with CLR, then shook in a jar with Bar Keepers Friend. Still many of the quarters and dimes are reddish purple. Is there any way to get them back to silver color?

 

[G.A.P.metal]

stick them in a CoinStar and turn them into green!
Gary