We claim the ornamental design for a masonry block, as shown and described.
FIG. 1 is a perspective view of a masonry block;
FIG. 2 is a front view of the masonry block, as shown in FIG. 1;
FIG. 3 is a rear view of the masonry block, shown in FIG. 1;
FIG. 4 is a first side view of the masonry block, shown in FIG. 1;
FIG. 5 is a second side view of the masonry block, shown in FIG. 1;
FIG. 6 is a top view of the masonry block, shown in FIG. 1;
FIG. 7 is a bottom view of the masonry block, shown in FIG. 1; and,
FIG. 8 is an enlarged view of the circular detail, shown in FIG. 1.
The dashed lines shown in the figures represent unclaimed portions of the masonry block and form no part of the claimed design. The broken line circle in FIGS. 1 and 8 depicts the limits of the enlarged view and forms no part of the claimed design.