I checked the known VAMS and don't see any mention of this, so if it is a mint error, it could be a newly discovered
VAM. Perhaps though if it is a die chip or
Cud plug, it may be so random that it wouldn't reproduce another one, therefore it would likely not be considered a
VAM but rather just a random occurrence. Not sure if it's value is greater due to this condition, but it's very interesting nonetheless so congrats on discovering it!