I still have a few washers I messed up stamping and I immediately wondered what I should do with them.  Welding is a good idea too.  And to fillippone, believe me or not I have not even thought about disposing of them in toilets or burying them in the ground, one washer every trip.

But being the freak that I am, I agree with n0nce.  Even if it is practically impossible to find even 4 of them, probably even 3, it would drive me nuts knowing that the washers are not in my household anymore but sitting outside where anyone could pick them up with my seed still stamped onto them.

My idea of disposing of washers comes from the fear that someone finds my empty seed and gets to see and analyze the history of my coins.  Welding, throwing them away or burying them separately miles away each, stamping multiple letters to make the letters unrecognizable.  I love brainstorming.

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Regards,
PrivacyG