The ornamental design for an article of jewelry, as shown and described.
FIG. 1 is a front elevation view of an article of jewelry showing my new design;
FIG. 2 is a left side view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof; and,
FIG. 6 is a rear elevation view thereof.
The broken lines in all figures are included for the purpose of illustrating portions of the article for jewelry that form no part of the claimed design.