I bought several silver Washington quarters, ranging in dates from 1934 to 1961 because I'm working on a date and mint mark set of them. I got them off of eBay, and they arrived today. When I first glanced through them, I thought I saw scratches on the reverse of the 1955 (Philadelphia mint), but when I looked at them through my loupe, I could tell they were raised metal, not scratches. Here are the pics, taken through my cheap digital microscope:
