Probably PMD. Sure, those coins are supposed to have a central hole, but a plain round one. Don't really see how something like that could have happened at the mint ... Christian
Check this site out. https://www.catawiki.com/catalog/coins/countries/luxembourg/1519969-luxembourg-10-centimes-1915
Right, that is what the coin is supposed to look like. But what makes you think it could be a mint error? Not saying it can't be; I just believe that PMD is much more likely ... Christian