The Essentials You Need To Know When Purchasing and Caring For Your Diamond.
Diamond Weight

Diamond Carat Weight

Diamonds are weighed in carats. The term carat originated in ancient times when gemstones were weighted against the carob bean. Each bean weighed about one carat. In 1913, carat weight was standardized internationally and adapted to the metric system. One carat equals 0.2 grams.

The weight of a diamond is often confused with its face-up size as you would see it in a ring. Diamonds are often cut deeper to conserve weight. This extra weight inflates the price of the diamond but does not add to its size or beauty. As outlined in our cut section, diamonds cut deeper than they should will also leak light and appear less brilliant than diamonds of proper proportion. For this reason it is often the case that a better cut diamond of lower carat weight will appear larger and sparkle more than a poorly cut diamond weighing more.

Fractional Carat Weight Equivalence Chart

The weight of diamonds in jewelry is often averaged and expressed as a fraction The chart to the right outlines the carat weight ranges Amberley West assigns to the fractional weights used on our website.

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Fractional Carat Weight Equivalence
1/10 Ct 0.09 to 0.11 carat
1/8 Ct 0.12 to 0.13 carat
1/7 Ct 0.14 to 0.17 carat
1/5 Ct 0.18 to 0.22 carat
1/4 Ct 0.23 to 0.28 carat
1/3 Ct 0.29 to 0.36 carat
3/8 Ct 0.37 to 0.44 carat
1/2 Ct 0.45 to 0.58 carat
5/8 Ct 0.59 to 0.69 carat
3/4 Ct 0.70 to 0.82 carat
7/8 Ct 0.83 to 0.94 carat
1 Ct 0.95 to 1.10 carat
1 1/4 Ct 1.20 to 1.39 carat
1 1/2 Ct 1.45 to 1.59 carat
1 3/4 Ct 1.70 to 1.79 carat
2 Ct 1.95 to 2.10 carat