I claim the ornamental design for a medallion stand, as shown and described.
FIG. 1 is a left side front perspective view of a first embodiment of a medallion stand showing my design;
FIG. 2 is a front elevation view of the first embodiment;
FIG. 3 is a right side front perspective view of the first embodiment;
FIG. 4 is a top side rear perspective view of the first embodiment;
FIG. 5 is a bottom side rear perspective view of the first embodiment; and,
FIG. 6 is a left elevation view of the first embodiment, the right elevation view of the first embodiment being a mirror image thereof, and therefore is not shown.
The broken lines shown in the drawings illustrate portions of the medallion stand that form no part of the claimed design.