3" Curb Chain Extender with Lobster Clasp 1.8mm

Since the varying densities of different stone materials and also the varying depths of different cutting styles can result in a significantly different, even between stones with a similar carat weight. 

Estimating Weights for Standard Faceted Cut Gemstones

Rounds		Squares / Pricess		Ovals
Size	Weight	Size	Weight	Size	Weight
1.6 mm	.02 carat	5 mm	.75 carat	5 x 3 mm	.25 carat
2 mm	.03 carat	6 mm	1.3 carat	6 x 4 mm	.5 carat
2.5 mm	.06 carat	7 mm	2.05 carat	7 x 5 mm	1.0 carat
3 mm	.10 carat	8 mm	2.9 carat	8 x 6 mm	1.5 carat
3.5 mm	.16 carat	9 mm	4.4 carat	9 x 7 mm	2.5 carat
4 mm	.25 carat	10 mm	6.0 carat	10 x 8 mm	3.0 carat
4.5 mm	.33 carat	11 mm	8.0 carat	11 x 9 mm	4.0 carat
5 mm	.50 carat	12 mm	10.35 carat	12 x 10 mm	5.0 carat
5.5 mm	.65 carat	13 mm	13.2 carat	14 x 10 mm	6.0 carat
6 mm	.75 carat	14 mm	16.5 carat	14 x 12 mm	8.0 carat
6.5 mm	1.0 carat	15 mm	20.25 carat	16 x 12 mm	10.5 carat
7 mm	1.25 carat	16 mm	24.6 carat	18 x 13 mm	14.2 carat
8 mm	2.0 carat
9 mm	2.75 carat
10 mm	3.5 carat
11 mm	4.6 carat
12 mm	6.0 carat
13 mm	7.75 carat
14 mm	9.65 carat
15 mm	11.85 carat
16 mm	16 carat
17 mm	17.25 carat
18 mm	20.5 carat
19 mm	24.0 carat
20 mm	28.0 carat
21 mm	34.8 carat
22 mm	41.8 carat
23 mm	49.8 carat
24 mm	57.9 carat
25 mm	68.7 carat

 

Emerald		Pear		Marquis
6 x 4 mm	.5 carat	6 x 5 mm	.7 carat	4 x 2 mm	.10 carat
7 x 5 mm	1.0 carat	7 x 5 mm	.75 carat	5 x 2.5 mm	.25 carat
8 x 6 mm	1.5 carat	8 x 5 mm	1.0 carat	6 x 3 mm	.30 carat
9 x 7 mm	2.5 carat	9 x 6 mm	1.5 carat	8 x 4 mm	.75 carat
10 x 8 mm	3.0 carat	10 x 7 mm	2.0 carat	10 x 5 mm	1.0 carat
11 x 9 mm	4.0 carat	11 x 7 mm	2.25 carat	12 x 6 mm	2.0 carat
12 x 10 mm	5.0 carat	12 x 8 mm	3.0 carat	14 x 7 mm	3.0 carat
14 x 10 mm	6.0 carat	13 x 9 mm	3.5 carat	16 x 8 mm	4.0 carat
14 x 12 mm	8.0 carat	15 x 10 mm	5.5 carat	18 x 9 mm	6.0 carat
16 x 12 mm	10.5 carat	16 x 12 mm	8.6 carat	20 x 10 mm	8.5 carat
18 x 13 mm	14.2 carat	18 x 13 mm	12 carat
20 x 15 mm	20.3 carat	20 x 15 mm	17.3 carat
25 x 18 mm	52.2 carat	22 x 15 mm	18.7 carat
25 x 18 mm	30.6 carat
30 x 22 mm	54.5 carat

🔰🔰 Mass-produced jewelry settings come in standard gem sizes. If a gem won’’t fit in a standard setting, you should have a setting custom made.