Gold purity is measured in karats with 24 karats representing the highest value. Gold jewelry marked "750" or "18k" indicates a blended metal consisting of 75% gold and 25% other alloys or elements.

Breguet is marking its 250th anniversary with a new watch called the Classique Souscription 2025. Made from a new 18K gold alloy that is less yellow than traditional gold, the timepiece is ...