How big is a 1ct diamond?

How big is a 1ct diamond?

The important thing to remember is that carat is a weight measurement (equal to 0.2gms) & not a size. This means different shapes & cuts of Diamond are different sizes even if they all weigh 1ct.

Below is a guide to 1ct diamond sizes based on well cut & proportioned stones:

• 1ct round brilliant cut diamond: 6.3mm
• 1ct princess cut diamond (square): 5.4mm
• 1ct oval cut diamond (vary due to different widths): 8.3mm x 5.6mm
• 1ct emerald cut diamond (vary due to different widths): 7mm x 4.7mm
• 1ct pear cut diamond (vary due to different widths): 8.9mm x 5.5mm
• 1ct marquise cut diamond (vary due to different widths): 10.3mm x 5.3mm

Do note if a diamond is badly cut or proportioned (for example it is too deep, too shallow or has bad symmetry) then these measurements will change.

Some people think it is a good idea to buy a shallow diamond that looks like a 1ct stone but weighs less in order to save money. This is actually a terrible idea because badly proportioned diamonds have far less sparkle.