What is ct in diamonds?

CT stands for carat, which is the unit of weight used for diamonds and other gemstones. One carat is equal to 0.2 grams, and is divided into 100 points. For example, a 0.50 carat diamond is also known as a 50-point diamond.

The carat weight of a diamond is one of the most important factors in determining its value, along with cut, clarity, and color. Diamonds over one carat are considered to be "large".