Stone Weight Chart

Calibrated Size Charts for Gemstones to be set in Standard Jewelry Mountings

Oval CutOval Cut

Calibrated Size Chart for Standard Jewelry Mountings (approximate weights)

Size in mm
Weight in carat
5×3 6×4 7×5 8×6 9×7 10×8 11×9 12×10 14×12
Alexandrite .30 .51 .80 1.45 2.00 3.60 4.25 6.00 8.90
Amethyst .23 .45 .85 1.25 1.75 2.40 3.20 4.50 6.50
Aquamarine .20 .40 .75 1.10 1.75 2.25 3.00 4.50 6.75
Citrine .23 .45 .85 1.25 1.75 2.40 3.25 4.20 5.20
Diamond .25 .50 .75 1.40 2.00 3.00 4.00 5.00 8.00
Emerald .25 .52 .85 1.26 1.90 2.60 3.75 5.00 7.50
Pyrope Garnet .25 .55 1.00 1.40 2.10 2.80 3.75 5.00 7.00
Iolite .21 .40 .63 1.02
Opal .16 .28 .47 .78 1.10 1.65 2.15 3.00 4.00
Peridot .28 .50 .95 1.35 2.00 2.50 3.50 4.00 6.00
Ruby .35 .60 1.06 1.55 2.20 3.15 3.80 6.00 7.25
Sapphire .35 .60 1.00 1.55 2.20 3.15 3.80 6.00 7.25
Tanzanite .20 .48 .89 1.35
Topaz .28 .57 1.10 1.60 2.50 3.50 4.50 6.00 8.80
Tourmaline .25 .50 .90 1.18 2.30 2.90 3.50 5.25 6.80
Tsavorite .28 .52 .75
Zircon .40 .75 1.45 2.00 2.85 4.00 5.60 7.50 8.20

 

Round CutRound Cut

Calibrated Size Chart for Standard Jewelry Mountings (approximate weights)

Size in mm
Weight in carat
2 3 4 5 6 6.5 7 8 10
Alexandrite .04 .12 .35 .63 1.30 1.86 2.15 2.90 5.20
Amethyst .04 .10 .20 .40 .70 1.10 1.30 1.80 3.30
Aquamarine .04 .10 .25 .45 .75 1.31 1.60 2.40 3.50
Citrine .04 .10 .20 .40 .70 1.10 1.30 1.80 3.30
Diamond .03 .10 .23 .47 .80 1.00 1.25 1.90 3.50
Emerald .04 .12 .27 .48 .80 1.26 1.70 2.50 6.10
Pyrope Garnet .05 .13 .30 .60 1.00 1.40 1.60 2.50 5.75
Opal .02 .09 .16 .34 .57 .75 .83 1.30 2.00
Peridot .05 .12 .26 .50 .85 1.11 1.25 2.00 5.25
Ruby .05 .15 .34 .65 1.05 1.41 1.60 2.25 4.50
Sapphire .05 .15 .34 .65 1.05 1.41 1.60 2.25 4.50
Topaz .04 .11 .30 .56 1.00 1.36 1.55 2.50 5.75
Tourmaline .04 .12 .24 .45 .75 1.28 1.55 2.00 3.00
Zircon .06 .17 .36 .69 1.25 1.58 1.75 2.60 5.00

 

Pear CutPear Cut

Calibrated Size Chart for Standard Jewelry Mountings (approximate weights)

Size in mm
Weight in carat
5×3 6×4 7×5 8×6 9×6 10×7 12×8 14×9
Alexandrite .30 .50 .85 1.10 2.10 3.60 6.60 8.80
Amethyst .20 .35 .65 .85 1.25 1.70 4.00 5.00
Aquamarine .20 .35 .65 .90 1.30 1.85 4.20 5.60
Citrine .20 .35 .65 .85 1.30 1.70 4.00 5.00
Diamond .25 .50 .75 1.00 1.50 2.00 3.50 5.00
Emerald .25 .45 .70 1.05 1.70 2.60 4.15 6.10
Pyrope Garnet .25 .40 1.00 1.15 1.30 1.80 3.50 5.80
Opal .13 .22 .35 .50 .70 1.03 1.40 2.45
Peridot .25 .45 .70 .80 1.10 1.40 3.40 4.75
Ruby .30 .50 .75 1.00 1.85 2.50 4.75 7.90
Sapphire .30 .50 .75 1.00 1.85 2.50 4.75 7.90
Topaz .25 .50 1.00 1.10 2.00 3.50 6.50 8.50
Tourmaline .35 .45 .60 .90 1.10 1.40 2.80 6.75
Zircon .30 .70 1.00 1.30 2.60 4.00 5.25 7.50

 

Octagon GemstonesOctagon / Emerald Cut

Calibrated Size Chart for Standard Jewelry Mountings (approximate weights)

Size in mm
Weight in carat
5×3 6×4 7×5 8×6 9×7 10×8 11×9 12×10 14×12
Alexandrite .40 .70 1.30 2.60 3.60 4.20 6.00 8.50 9.90
Amethyst .35 .55 1.10 1.60 2.25 2.90 4.20 5.60 7.25
Aquamarine .25 .50 .80 1.40 2.00 3.00 4.30 4.75 7.75
Citrine .35 .55 1.00 1.60 2.25 2.90 4.20 5.60 7.25
Diamond .25 .50 1.00 1.50 3.00 4.00 5.00 7.80 8.80
Emerald .30 .60 .90 1.80 2.31 3.15 4.50 5.25 5.80
Pyrope Garnet .40 .80 1.20 1.70 2.50 3.50 4.30 6.35 9.00
Peridot .35 .60 1.00 1.70 2.25 3.80 5.25 6.25 8.80
Ruby .55 .75 1.15 1.60 2.30 2.75 4.00 6.25 9.00
Sapphire .55 .75 1.15 1.75 2.30 2.75 4.00 6.25 9.00
Topaz .40 .65 1.25 2.40 3.40 4.00 5.75 8.00 9.50
Tourmaline .30 .60 1.60 2.15 2.80 3.60 4.30 5.20 8.50
Zircon .60 .85 1.70 2.35 3.90 450 6.20 7.01 8.95

 

Marquise CutMarquise Cut

Calibrated Size Chart for Standard Jewelry Mountings (approximate weights)

Size in mm
Weight in carat
4×2 5×3 6×3 7×3.5 8×4 10×5 12×6 14×7
Alexandrite .07 .20 .30 .50 .70 1.25 2.10 3.50
Amethyst .10 .15 .20 .34 .48 .90 1.59 2.45
Aquamarine .08 .14 .20 .25 .50 .80 1.50 2.75
Citrine .10 .15 .20 .35 .50 .90 1.59 2.45
Diamond .12 .18 .25 .37 .50 1.00 2.00 3.00
Emerald .09 .19 .30 .45 .60 1.40 1.80 2.80
Pyrope Garnet .09 .16 .25 .42 .60 1.20 2.00 2.85
Opal .09 .13 .17 .27 .37 .59 1.00 1.25
Peridot .10 .17 .25 .37 .50 1.00 2.00 2.55
Ruby .13 .24 .35 .55 .75 1.15 2.20 3.00
Sapphire .13 .24 .35 .55 .75 1.15 2.20 3.00
Topaz .07 .17 .30 .50 .70 1.20 2.00 3.40
Tourmaline .10 .20 .30 .45 .60 .85 1.55 2.20
Zircon .13 .23 .33 .55 .75 1.25 1.95 3.00