The Journal

To measure ring size at home, wrap a thin paper strip around the base of your finger, mark where it overlaps and measure that length in millimetres: this is your inner circumference. Subtract 40 for an approximate Indian size, so 60 mm is about size 20. Or measure the inside diameter of a ring that already fits.

For most men, 925 sterling silver is the better choice for everyday style pieces and 18K gold is the better choice for a ring or chain meant to last a lifetime with little upkeep. Gold holds its metal value and does not tarnish; silver costs far less, so the same budget buys more design and stones. Many men wear both.

To choose a men's diamond ring, decide five things in order: the style of ring, black or white stones, natural or lab-grown origin, the metal, and only then the 4Cs. Most men's diamond rings are bands set with many small stones, so a protective setting and a correct fit matter more than grading reports.