FIG. 1 is a top, front, and right side perspective view of an oval cushion stone;
FIG. 2 is a bottom, rear, and left side perspective view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom view thereof; and
FIG. 5 is a left side view thereof, the right side view being a mirror image thereof;
FIG. 6 is a front side view thereof, the rear side view being a mirror image thereof;
FIG. 7 is a top, front, and right side perspective view of an alternative embodiment of an oval cushion stone;
FIG. 8 is a bottom, rear, and left side perspective view thereof;
FIG. 9 is a top view thereof;
FIG. 10 is a bottom view thereof; and
FIG. 11 is a left side view thereof, the right side view being a mirror image thereof; and,
FIG. 12 is a front side view thereof, the rear side view being a mirror image thereof.
The broken lines in FIGS. 1, 2, 4, 5, 6, 7, 8, 10, 11 and 12 depict portions of the oval cushion stone that form no part of the claimed design.