I did have 4 2018 D mint mark but it looks like I accidentally tossed 2 in the spend jar. Let me know what you think doubled or machine. Hope the pictures are good enough I had to borrow a usb camera.
You can toss those two into the spend jar with the other two. Unless, of course you need them as hole fillers. Keep looking.
It's hard to tell the difference between what I'm seeing, my pictures and the pictures I just now enclosed from varietyvista.