So, I was playing on eevee and had nothing better to do, so I mined 64 fossils with fortune 3 and had a ton to clean. I got 18 cleaners in a line and started spamming my fossils in and cleaning them. Lo and behold, when my shieldon fossil got down to 1 fossil left, it let me keep putting it in the cleaners. it let me duplicate the same fossil like 30 times to give me more cleaned fossils. I told Winglet and here we are. So, I don't know what caused it, but I was spam right clicking to put fossils in and take them out so it might have something to do with it. Also, when I threw the glitched fossil from my inventory and picked it back up again, it fixed the glitch and I couldn't duplicate it anymore.

Marking this ticket as Expired because of age and being unable to reproduce the ticket in 7.3.1, if this is still occurring in 7.3.1 please make a new ticket