You've likely seen "CTW" on diamond jewelry labels, but not everyone knows what it stands for, and it gets a bit tricky when it applies to earrings. 

The abbreviation CTW stands for "Carat Total Weight" and is the sum of the weights of all diamonds in the piece. Earrings are sold as a pair, and therefore their Carat Total Weight is the combined carat weight of both diamonds. For example, let's look at a pair of 1CTW studs. Each earring would be about a half carat (0.50), equaling one Total Carat Weight. 

Above is a pair of our lab-grown diamond studs at 1/3 CTW. This means that each earring has a carat weight of between 0.14 - 0.17, with a combined carat total weight of 1/3, or between 0.29ct - 0.34ct. 

Of course, there are other types of earrings as well that include multiple stones, like in cluster earrings or halo earrings. 

You may see halo earrings that say "1 CTW", which means that all of the diamonds, both center and halo, in both of the earrings, add up to 1.00 Carat Total Weight. Below is a good example of 1.00 CTW halo earrings (Rounded Square Double Halo Earrings).

Also something to consider is that all of these "total weights" are always an approximate, or a range, as long as the stated Carat Total Weight is within the range accepted by the FTC. As an example, 1 CTW may be within 0.95 - 1.10 carat total weight, and 1/2 CTW may be within 0.45 - 0.59 CTW. 

Hopefully, this little bit of knowledge on carat total weight has been helpful and will guide you to a more educated purchase when pursuing diamond earrings! Click here to see our collection of lab-grown diamond earrings.