1988 Penny Circle Anomaly?

If you spotted a UFO, you wouldn't go anywhere...

Merclover, thank you for helping keep this place drama free with that apology. It's what this forum such a great place to learn.

I like "Crop Circles". Very mysterious.

Ok , I have done a little turning on a wood lathe but I've never used a metal lathe.
That said , when you want to center some stock on a lathe you can drill a small hole in the end of your stock where you want center to be and fit it over a centering tool like this


At any point the stock can be remounted on the lathe using this point and hole combo.
It sorta makes sense that if a coned shape piece of die stock needed to be remounted in a lathe the point of the stock would be fitted into a small hole to center it. Tighten the metal stock on the lathe and you have nice little circle impression at the center tip of the die cone that leaves a circle on the final coins.
Food for thought

Whatever caused them, I still keep mine. There are several known years and denominations but compared to other varieties/errors, they are quite scarce. Since searching coins and these being "a thing" I found maybe 4 and my last one was in 2020