1.8 Carat diamonds weigh approximately 360 milligrams. Carat is the standard unit used to measure the weight of diamonds. The actual dimensions of a 1.8 Carat diamond depend on its size, cut, and clarity. Typically, the diameter of a 1.8 Carat diamond ranges around 7.77mm. For detailed information and to purchase 1.8 Carat diamonds, please visit our online store.