APPROXIMATE CARAT WEIGHT CHART FOR SPECIFIC GEMSTONES (& AVERAGE)

This Approximate Carat Weight Chart for various Gemstone materials in relation to their Shape and MM Size serves to help when needing to get a ballpark idea of what an item will cost when multiplying the items carat weight by the items price per carat. The last column is an average of the various gemstone materials weight for a particular shape and size. Please keep in mind that the individual cutting of any specific gemstone will have a great effect on its resulting carat weight. A shallow stone for example will end up weighing less where a heavy belly cut stone will weigh more.

Alexandrite Amethyst Citrine Aquamarine Diamond Emerald Garnet Opal Peridot Ruby Sapphire Tanzanite Topaz Tourmaline Zircon Blue Average
ROUND ROUND
2.00 mm 0.04 0.04 0.04 0.04 0.04 0.05 0.02 0.05 0.05 0.05 0.04 0.04 0.06 0.05 2.00 mm
3.00 mm 0.12 0.10 0.10 0.10 0.12 0.13 0.09 0.12 0.15 0.12 0.11 0.12 0.17 0.12 3.00 mm
4.00 mm 0.35 0.20 0.25 0.23 0.27 0.30 0.16 0.26 0.34 0.29 0.30 0.24 0.36 0.27 4.00 mm
5.00 mm 0.63 0.40 0.45 0.47 0.48 0.60 0.34 0.50 0.65 0.48 0.56 0.45 0.69 0.53 5.00 mm
6.00 mm 1.30 0.70 0.75 0.90 0.80 1.00 0.57 0.85 1.05 0.86 1.00 0.75 1.25 0.90 6.00 mm
7.00 mm 2.15 1.30 1.60 1.35 1.70 1.60 0.83 1.25 1.60 1.35 1.55 1.55 1.75 1.51 7.00 mm
8.00 mm ------- 1.80 2.40 1.90 2.50 2.50 1.30 2.00 2.25 1.85 2.50 2.00 2.60 2.21 8.00 mm
10.00 mm ------- 3.30 3.50 4.25 6.10 5.75 2.00 5.25 4.50 3.60 5.75 3.00 5.00 4.52 10.00 mm
OVAL OVAL
5x3 mm 0.30 0.23 0.20 0.25 0.28 0.25 0.16 0.28 0.35 0.24 0.27 0.25 0.40 0.28 5x3 mm
6x4 mm 0.61 0.45 0.40 0.50 0.52 0.55 0.28 0.50 0.60 0.48 0.57 0.50 0.75 0.53 6x4 mm
7x5 mm 0.80 0.85 0.75 0.75 0.85 1.00 0.47 0.95 1.00 0.75 1.10 0.90 1.45 0.95 7x5 mm
8x6 mm 1.45 1.25 1.10 1.40 1.00 1.40 0.78 1.35 1.55 1.25 1.60 1.18 2.00 1.39 8x6 mm
9x7 mm 2.00 1.75 1.75 2.00 1.60 2.10 1.10 2.00 2.20 1.80 2.50 2.30 2.85 2.08 9x7 mm
10x8 mm 3.60 2.40 2.25 3.00 2.25 2.80 1.65 2.50 3.15 2.40 3.50 2.90 4.00 2.86 10x8 mm
11x9 mm 4.25 3.24 3.00 4.00 3.75 3.75 2.15 3.50 3.80 3.30 4.50 3.50 5.60 3.80 11x9 mm
12x10 mm 6.00 4.35 4.50 5.00 5.00 5.00 3.00 4.00 6.00 4.40 6.00 5.25 7.50 5.25 12x10 mm
14x10 mm 8.90 5.85 6.75 8.00 7.50 7.00 4.00 6.00 7.25 5.90 8.80 6.80 8.20 7.10 14x10 mm
16x12 mm ------- 10.00 10.15 11.50 12.00 10.00 5.25 9.50 12.00 12.00 12.00 8.50 13.50 10.93 16x12 mm
18x13 mm ------- 12.38 10.57 16.00 14.50 13.25 5.75 13.00 13.00 14.00 17.00 12.00 14.50 13.46 18x13 mm
20x15 mm ------- 18.00 14.50 21.50 18.00 20.00 9.90 20.00 20.00 19.00 22.00 18.00 23.00 19.42 20x15 mm
OCTAGON OCTAGON
5x3 mm 0.40 0.35 0.25 0.25 0.30 0.40 ------- 0.35 0.55 0.38 0.40 0.30 0.60 0.39 5x3 mm
6x4 mm 0.70 0.55 0.50 0.50 0.60 0.80 ------- 0.60 0.75 0.58 0.65 0.60 0.85 0.64 6x4 mm
7x5 mm 1.30 1.00 0.80 1.00 0.90 1.20 ------- 1.00 1.15 1.03 1.25 1.60 1.70 1.15 7x5 mm
8x6 mm 2.60 1.60 1.40 1.50 1.80 1.70 ------- 1.70 1.68 1.65 2.40 2.15 2.35 1.80 8x6 mm
9x7 mm 3.60 2.25 2.00 3.00 2.31 2.50 ------- 2.25 2.30 2.30 3.40 2.80 3.90 2.61 9x7 mm
10x8 mm 4.20 2.90 3.00 4.00 3.15 3.50 ------- 3.80 2.75 2.95 4.00 3.60 4.50 3.40 10x8 mm
11x9 mm 6.00 4.20 4.30 5.00 4.50 4.30 ------- 5.25 4.00 4.25 5.75 4.30 6.20 4.67 11x9 mm
12x10 mm 8.50 5.60 4.75 7.80 5.25 6.35 ------- 6.25 6.25 5.65 8.00 5.20 7.01 6.19 12x10 mm
14x10 mm 9.90 7.25 7.75 8.80 5.80 9.00 ------- 8.80 9.00 7.30 9.50 8.50 8.95 8.30 14x10 mm
16x12 mm ------- 13.00 13.50 13.00 14.00 17.50 ------- 17.00 12.50 14.00 14.00 13.00 14.30 13.94 16x12 mm
18x13 mm ------- 17.00 17.00 20.00 17.50 21.00 ------- 20.00 18.70 18.00 21.00 16.50 19.90 18.69 18x13 mm
20x15 mm ------- 22.00 22.00 25.50 22.50 27.00 ------- 26.00 27.00 24.00 26.00 24.90 28.70 25.05 20x15 mm
MARQUISE MARQUISE
4x2 mm 0.07 0.10 0.08 0.12 0.09 0.09 0.09 0.10 0.13 0.07 0.07 0.10 0.13 0.10 4x2 mm
6x3 mm 0.30 0.20 0.20 0.25 0.30 0.25 0.17 0.25 0.35 0.23 0.30 0.30 0.33 0.27 6x3 mm
8x4 mm 0.70 0.50 0.50 0.50 0.60 0.60 0.37 0.50 0.75 0.51 0.70 0.60 0.75 0.60 8x4 mm
10x5 mm 1.25 0.90 0.80 1.00 1.10 1.20 0.59 1.00 1.15 1.25 1.20 0.85 1.25 1.04 10x5 mm
12x6 mm 2.10 1.59 1.50 2.00 1.80 2.00 1.00 2.00 2.20 1.63 2.00 1.55 1.95 1.87 12x6 mm
14x7 mm ------- 2.45 2.75 3.00 2.80 2.85 1.25 2.55 3.00 2.50 3.40 2.20 3.00 2.79 14x7 mm
PEAR PEAR
5x3 mm 0.30 0.02 0.20 0.25 0.25 0.25 0.13 0.25 0.30 0.20 0.25 0.35 0.30 0.26 5x3 mm
6x4 mm 0.50 0.35 0.35 0.50 0.45 0.40 0.22 0.45 0.50 0.40 0.50 0.45 0.70 0.46 6x4 mm
7x5 mm 0.85 0.65 0.65 0.75 0.70 1.00 0.35 0.70 0.75 0.75 1.00 0.60 1.00 0.77 7x5 mm
8x5 mm 1.10 0.85 0.90 1.00 1.05 1.15 0.50 0.80 1.00 0.90 1.10 0.90 1.30 0.99 8x5 mm
9x6 mm 2.10 1.28 1.30 1.50 1.70 1.30 0.70 1.10 1.85 1.42 2.00 1.10 2.60 1.57 9x6 mm
10x7 mm 3.60 1.70 1.85 2.00 2.60 1.80 1.03 1.40 2.50 1.78 3.50 1.40 4.00 2.25 10x7 mm
13x8 mm ------- 4.00 4.20 3.50 4.15 3.50 1.40 3.40 4.75 4.00 6.50 2.80 5.25 4.23 13x8 mm
14x10 mm ------- 5.00 5.60 5.00 6.10 5.80 2.45 4.75 7.90 5.75 8.50 6.75 7.50 6.32 14x10 mm
HEART HEART
3x3 mm ------- 0.12 0.09 0.10 0.12 0.16 0.07 0.15 0.15 0.10 0.18 0.10 0.17 0.12 3x3 mm
4x4 mm ------- 0.20 0.21 0.23 0.25 0.30 0.17 0.25 0.36 0.21 0.30 0.25 0.36 0.27 4x4 mm
5x5 mm ------- 0.40 0.39 0.47 0.50 0.50 0.29 0.45 0.60 0.37 0.55 0.40 0.69 0.48 5x5 mm
6x6 mm ------- 0.70 0.61 0.90 0.80 0.85 0.42 0.80 1.00 0.61 1.00 0.77 1.25 0.83 6x6 mm
7x7 mm ------- 1.15 1.00 1.35 ------- 1.30 0.70 1.30 1.60 1.12 1.60 1.12 1.75 1.31 7x7 mm
8X8 mm ------- 1.54 1.30 1.90 ------- 1.85 1.00 2.80 2.25 1.56 2.25 1.58 2.60 1.84 8x8 mm
9x9 mm ------- 2.15 2.20 ------- ------- 2.70 ------- ------- 2.20 3.20 ------- 2.20 ------- 2.48 9x9 mm
10x10 mm ------- 3.05 3.00 ------- ------- 3.80 1.70 ------- 3.10 4.30 ------- 3.10 ------- 3.44 10x10 mm