How big is a carat diamond?

The diameter of a standard round diamond for one carat is 6.49 mm, and that for one carat (1ct) is 0.2 g. ..

But it should be noted that diamonds come in different shapes and sizes. For example, a one-carat round diamond has a diameter of 6.49 mm, while a princess square diamond has a diameter of 5.5 mm..

Other shapes and diameters of a carat diamond are also different, namely: emerald 5 mm, pear 5.5 mm, oval 6.5 mm, heart 6.5 mm, olive tip 5.5 mm and ruby 4.75 mm. ..