There’s a black dot at the bottom of the mug which I have pictured. Not sure what it is exactly. I bought it new so it came like that. More Rae Dunn items available in my closet- bundles welcome! Buy 2 or more items to only pay shipping once! *All items will be packaged with care! *Please note: Rae Dunn pottery is known to have slight imperfections and markings as part of its uniqueness and design. This is why each piece is so special!