They are specially made coins not intended for circulatuon. They have a mirror - like finish. Regular business strike coins are ones meant for circulation.
Your best bet now is to take them to a coin shop or a knowledgeable collector to examine. I'd the flip is wrong and is missing the denomination, then it is suspect.
Okay, then the next thing I want to ask........ When you flip it side-to-side with the obverse perfectly vertical, is the reverse also perfectly vertical? Or, is it tilted slightly, even just a little? Chris
Forget I asked that. It was a pointless question. What I was about to suggest, like AWORDCREATED already mentioned is that it could be the result of a rotated die. The fact that it also could be a grease-filled die is just coincidental, but it could make it very interesting if it has both errors at the same time. You really should take it (or send it) to someone for examination. Chris
Looked way off to me, so much so that I did a search on the net to see if anyone had posted about them. How I came across this thread.
I have 1999 Susan B Anthony Proof sets, and neither has the 180 degree error, and both have "ONE DOLLAR" stamped on the back.
if you took them to a shop as suggested...probably not. every coin store I have ever been in knows nothing of errors.