Size is as-packaged, or the diameter of loose marbles. ("D" is the diameter of round items other than marbles.)
These modern non-glass marbles are created with an old look and feel. They sport fading dye-jobs and are slightly out-of-round, like many vintage marbles from the late 19th and early 20th centuries. Some marbles have a star motif - these are mixed in and pulled out randomly, our choice of color please.