Quick and Easy Buying Guide
Carat weight: 1 carat = 200 milligrams = 6.5 mm diameter. Doubling weight doesn't double diameter.
Diamond clarity: FL/IF/VVS/VS = super expensive, near perfect. SI = best value if you can check a photo for obvious inclusions (defects).
Color: D-G = colorless, expensive, only if you have money to burn. H-J = best value. Can go lower in gold metal settings than white metal.
Cut: Better cut ratings let more light into a diamond, making it sparkle more. Very important property, don't skimp here.
Set a budget and minimum cut (Premium). Go J color for gold and I/H for white metals. Go searching for SI1/SI2 clarity diamonds at James Allen. Pick a diamond with small/no inclusions. Choose a ring setting and buy it risk-free (60-day returns).
2.80 Carat Princess Shape Diamond Actual Size
Carat weight isn't the be all and end all - the depth of the diamond's cut will also influence the apparent size of the diamond; a diamond like this 2.80 carat one will usually be around 16.0 mm . This picture will no doubt give you an approximate idea of how large a diamond will appear viewed on the hand, remember that the size of the ring you pick or need could be quite different in size to that shown in this image. Pictures can sometimes be notoriously deceptive - this one is pretty clear cut, but remember viewing the stone in person will give you a very different judgement of size to examining it on the web.