It appears to be rounded at the upper edges, I venture to say it has been manually removed. It is possible yes to not have reeding, that would be a broadstruk coin, or "out of collar" struck. The reeding is impressed by the collar upon striking. A planchet tho, will have quite visible layers, your coin is "wavy", this indicates the metal has been forced by the collar present, only way for that effect. Reeding has been filed smoother by slot/vending machines I bet.