The 2.5 Carat Diamonds is a popular diamond. A 2.5-carat diamond weighs approximately 500 milligrams. 2.5-carat diamonds are widely preferred for engagement rings. The cost of a 2.5-carat diamond depends on its weight as well as other factors such as cut, color, clarity, symmetry, and polish. Visit our online store for 2.5-carat diamonds and diamond jewelry.