Diamond Size Where You Live If you're from the Midwest or a smaller town, you'll notice that a 1 carat stone is still considered the “classic” weight. Look around and see what most of your social circle is sporting and you'll have a good idea if your one carat rock is considered large, geographically speaking.

On average, the retail price for one carat diamonds can be anywhere between $2,000 to $16,000, and between $8,000 to $72,000 for two carat diamonds . And of course, the retail price and the resale value of a diamond are very different things.

A 1 carat Emerald cut diamond measures around 7 by 5 mm, while the size range of a 1.5 carat Emerald cut diamond goes from 8.20 by 5.65mm to 8.40 by 5.85 mm.

One carat equals 0.200 grams or 1/5 gram and is subdivided into 100 points. For comparison, in units more familiar in the United States, one carat equals 0.007 ounce avoirdupois.