The ornamental design for a wrought ironballlamp, as shown and described.
FIG. 1 is a front perspective view of a wrought iron ball lamp showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a top view thereof;
FIG. 7 is a bottom view thereof; and,
FIG. 8 is an enlarged view thereof.
The broken lines shown in the drawings illustrate portions of the wrought iron ball lamp. The dot-dash-dot broken lines demarcate the enlarged view; all broken lines form no part of the claimed design.