1/2-carat diamonds are another name for half-carat diamonds. 5 diamonds, 0.5 carat diamonds, or diamonds of 50 points This round brilliant from James Allen and this cushion-cut diamond from Blue Nile are both stunning half-carat gems. For a half-carat diamond, refer to our diamond size chart above. For more information on half-carats, see our article on the different types of diamonds. Half-carat diamonds are the most common type of diamond and can be used in anything that requires a diamond of that weight. They are a popular choice for engagement rings because they are easy to buy and sell on the open market. The other type of diamond is a full carat (200 points). Half-cars usually cost less than full-carat diamonds but have less value if you ever want to sell them. The price of half-carats varies depending on the color and clarity. White diamonds tend to be more expensive than colored diamonds. Fancy color diamonds are also more expensive than simple color diamonds. In general, the lower the quality rating, the cheaper the stone will be. All things considered, half-carat diamonds offer excellent value for your money. There are many factors that go into determining a diamond's price, such as its cut, color, and clarity. But at the end of the day, it's all about the carat weight.