|
Diamonds & Gemstones Conversion Charts
Convert from milimeter measurement the carat weight of round cut diamonds to know the approximate carat weight or carat weight equivelent. The weights listed below for diamonds are averages only and based on their specific gravity. Stones that have a very deep or very shallow cut or a higher or lower specific gravity will vary from these estimated carat weights.
|
| Round Diamonds |
|
Round Diamonds |
Round
Cut |
Decimal
Inch |
 |
Round
Cut |
Decimal
Inch |
|
|
mm
width
|
Decimal width
|
Weight
|
mm
width
|
Decimal width
|
Weight |
| 1.0 mm |
.039 inch |
.005 carat |
4.8 mm |
|
.40 carat |
| 1.2 mm |
|
.008 carat |
4.9 mm |
|
.43 carat |
| 1.3 mm |
|
.01 carat |
5.0 mm |
.197 inch |
.47 carat |
| 1.5 mm |
|
.015 carat |
5.2 mm |
.205 inch |
1/2 carat |
| 1.7 mm |
|
.02 carat |
5.4 mm |
|
.60 carat |
| 1.8 mm |
|
.025 carat |
5.5 mm |
|
.63 carat |
| 2.0 mm |
.079 inch |
.03 carat |
5.6 mm |
|
.65 carat |
| 2.1 mm |
|
.035 carat |
5.8 mm |
.228 inch |
3/4 carat |
| 2.2 mm |
|
.04 carat |
6.0 mm |
.236 inch |
.80 carat |
| 2.4 mm |
|
.05 carat |
6.2 mm |
|
.85 carat |
| 2.5 mm |
|
.06 carat |
6.4 mm |
|
.95 carat |
| 2.7 mm |
|
.07 carat |
6.5 mm |
.255 inch
or 1/4 inch |
1.00 carat |
| 2.8 mm |
|
.08 carat |
6.6 mm |
|
1.10 carat |
| 2.9 mm |
|
.09 carat |
6.8 mm |
|
1.17 carat |
| 3.0 mm |
.118 inch |
1/10 carat |
7.0 mm |
.276 inch |
1-1/4 carat |
| 3.1 mm |
|
.11 carat |
7.2 mm |
|
1.33 carat |
| 3.2 mm |
.125 inch
or 1/8 inch |
.12 carat |
7.4 mm |
.291 inch |
1-1/2 carat |
| 3.3 mm |
|
.14 carat |
7.6 mm |
|
1.60 carat |
| 3.4 mm |
|
.15 carat |
7.8 mm |
.307 inch |
1.75 carat |
| 3.5 mm |
|
.16 carat |
8.0 mm |
.315 inch |
1.90 carat |
| 3.6 mm |
|
.17 carat |
8.2 mm |
323 inch |
2.00 carat |
| 3.7 mm |
|
.18 carat |
8.4 mm |
|
2.15 carat |
| 3.8 mm |
.150 inch |
1/5 carat |
8.6 mm |
.338 inch |
2.25 carat |
| 3.9 mm |
|
.22 carat |
8.8 mm |
.346 inch |
2.50 carat |
| 4.0 mm |
.158 inch |
.23 carat |
9.0 mm |
.354 inch |
2.65 carat |
| 4.1 mm |
.162 inch |
1/4 carat |
9.2 mm |
|
2.85 carat |
| 4.2 mm |
|
.30 carat |
9.4 mm |
.370 inch |
3.00 carat |
| 4.4 mm |
.173 inch |
.33 carat |
9.6 mm |
|
3.15 carat |
| 4.5 mm |
|
.35 carat |
9.8 mm |
|
3.35 carat |
| 4.6 mm |
.181 inch |
1/3 carat |
10.0 mm |
.394 inch |
3-1/2 carat |
|
|
Round Stones
|
|
(approximate weights)
|
|
|
2mm
|
3mm
|
4mm
|
5mm
|
6mm
|
6.5mm
|
7mm
|
8mm
|
10mm
|
|
Alexandrite
|
.04 ct
|
.12 ct
|
.35 ct
|
.63 ct
|
1.30 ct
|
1.86 ct
|
2.15 ct
|
2.90 ct
|
5.20 ct
|
|
Amethyst
|
.04 ct
|
.10 ct
|
.20 ct
|
.40 ct
|
.70 ct
|
1.10 ct
|
1.30 ct
|
1.80 ct
|
3.30 ct
|
|
Aquamarine
|
.04 ct
|
.10 ct
|
.25 ct
|
.45 ct
|
.75 ct
|
1.31 ct
|
1.60 ct
|
2.40 ct
|
3.50 ct
|
|
Citrine
|
.04 ct
|
.10 ct
|
.20 ct
|
.40 ct
|
.70 ct
|
1.10 ct
|
1.30 ct
|
1.80 ct
|
3.30 ct
|
|
Emerald
|
.04 ct
|
.12 ct
|
.27 ct
|
.48 ct
|
.80 ct
|
1.26 ct
|
1.70 ct
|
2.50 ct
|
6.10 ct
|
|
Garnet
|
.05 ct
|
.13 ct
|
.30 ct
|
.60 ct
|
1.00 ct
|
1.40 ct
|
1.60 ct
|
2.50 ct
|
5.75 ct
|
|
Opal
|
.02 ct
|
.09 ct
|
.16 ct
|
.34 ct
|
.57 ct
|
.75 ct
|
.83 ct
|
1.30 ct
|
2.00 ct
|
|
Peridot
|
.05 ct
|
.12 ct
|
.26 ct
|
.50 ct
|
.85 ct
|
1.11 ct
|
1.25 ct
|
2.00 ct
|
5.25 ct
|
|
Ruby
|
.05 ct
|
.15 ct
|
.34 ct
|
.65 ct
|
1.05 ct
|
1.41 ct
|
1.60 ct
|
2.25 ct
|
4.50 ct
|
|
Sapphire
|
.05 ct
|
.15 ct
|
.34 ct
|
.65 ct
|
1.05 ct
|
1.41 ct
|
1.60 ct
|
2.25 ct
|
4.50 ct
|
|
Topaz
|
.04 ct
|
.11 ct
|
.30 ct
|
.56 ct
|
1.00 ct
|
1.36 ct
|
1.55 ct
|
2.50 ct
|
5.75 ct
|
|
Tourmaline
|
.04 ct
|
.12 ct
|
.24 ct
|
.45 ct
|
.75 ct
|
1.28 ct
|
1.55 ct
|
2.00 ct
|
3.00 ct
|
|
Zircon
|
.06 ct
|
.17 ct
|
.36 ct
|
.69 ct
|
1.25 ct
|
1.58 ct
|
1.75 ct
|
2.60 ct
|
5.00 ct
|
|
|
_th.jpg)
