Loose-Gems.com
Gemstone Weight Chart
Any and all weight charts are only guides for estimated weights. The reason for this is the way that a gemstone is cut has a lot to do with the weight of the stone. Crowns or pavilions that are heavy or light, thick or thin girdles all are determining factors on weight. The best method, is to weigh the stone with a scale designed to weigh gemstones.
The weights in the following charts are based on the stones shape and size and are estimates only. The weights will very for shape and size due to the proportions of the stone (girdle thickness, depth, style of cut, etc.) The following weight formulas will give a better weight estimate for specific stones.
Rounds |
2mm |
3mm |
4mm |
5mm |
6mm |
7mm |
8mm |
10mm |
| Alexandrite |
0.04 |
0.12 |
0.35 |
0.63 |
1.30 |
2.15 |
2.90 |
5.20 |
| Amethyst |
0.04 |
0.10 |
0.20 |
0.40 |
0.70 |
1.30 |
1.80 |
3.30 |
| Aqua |
0.04 |
0.10 |
0.25 |
0.45 |
0.75 |
1.60 |
2.40 |
3.50 |
| Citrine |
0.04 |
0.10 |
0.20 |
0.40 |
0.70 |
1.30 |
1.80 |
3.30 |
| Diamond |
0.04 |
0.10 |
0.23 |
0.47 |
0.85 |
1.25 |
1.90 |
4.25 |
| Emerald |
0.04 |
0.12 |
0.27 |
0.48 |
0.80 |
1.70 |
2.50 |
6.10 |
| Garnet |
0.05 |
0.13 |
0.30 |
0.60 |
1.00 |
1.60 |
2.50 |
5.75 |
| Opal |
0.02 |
0.09 |
0.16 |
0.34 |
0.57 |
0.83 |
1.30 |
2.00 |
| Peridot |
0.05 |
0.12 |
0.26 |
0.50 |
0.85 |
1.25 |
2.00 |
5.25 |
| Ruby |
0.05 |
0.15 |
0.34 |
0.65 |
1.05 |
1.60 |
2.25 |
4.50 |
| Sapphire |
0.05 |
0.15 |
0.34 |
0.65 |
1.05 |
1.60 |
2.25 |
4.50 |
| Topaz |
0.04 |
0.11 |
0.30 |
0.56 |
1.00 |
1.55 |
2.50 |
5.75 |
| Tourmaline |
0.04 |
0.12 |
0.24 |
0.45 |
0.75 |
1.55 |
2.00 |
3.00 |
| Zircon |
0.06 |
0.17 |
0.36 |
0.69 |
1.25 |
1.75 |
2.60 |
5.00 |
OVAL |
5X3mm |
6x4mm |
7x5mm |
8x6mm |
9x7mm |
10x8mm |
12x10 |
16x12 |
18x13 |
20x15 |
| Alexandrite |
0.30 |
0.60 |
0.80 |
1.45 |
2.00 |
3.60 |
6.00 |
12.50 |
18.00 |
24.00 |
| Amethyst |
0.23 |
0.45 |
0.85 |
1.25 |
1.75 |
2.40 |
4.50 |
11.00 |
14.00 |
16.00 |
| Aqua |
0.20 |
0.40 |
0.75 |
1.10 |
1.75 |
2.25 |
4.50 |
10.15 |
10.50 |
14.50 |
| Citrine |
0.23 |
0.45 |
0.85 |
1.25 |
1.75 |
2.40 |
4.20 |
9.00 |
10.50 |
20.00 |
| Diamond |
0.25 |
0.50 |
0.75 |
1.40 |
2.00 |
3.00 |
5.00 |
11.50 |
16.00 |
21.50 |
| Emerald |
0.28 |
0.52 |
0.85 |
1.26 |
1.90 |
2.60 |
5.00 |
12.00 |
14.50 |
18.00 |
| Garnet |
0.25 |
0.55 |
1.00 |
1.40 |
2.10 |
2.80 |
5.00 |
10.00 |
13.25 |
20.00 |
| Opal |
0.16 |
0.28 |
0.47 |
0.78 |
1.10 |
1.65 |
3.00 |
5.25 |
5.75 |
9.90 |
| Peridot |
0.28 |
0.50 |
0.95 |
1.35 |
2.00 |
2.50 |
4.00 |
9.50 |
13.00 |
20.00 |
| Ruby |
0.35 |
0.60 |
1.00 |
1.55 |
2.20 |
3.15 |
6.00 |
12.00 |
13.00 |
20.00 |
| Sapphire |
0.35 |
0.60 |
1.00 |
1.55 |
2.20 |
3.15 |
6.00 |
12.00 |
13.00 |
20.00 |
| Topaz |
0.27 |
0.57 |
1.10 |
1.60 |
2.50 |
3.50 |
6.00 |
12.00 |
17.00 |
22.00 |
| Tourmaline |
0.25 |
0.50 |
0.90 |
1.18 |
2.30 |
2.90 |
5.25 |
8.50 |
12.00 |
18.00 |
| Zircon |
0.40 |
0.75 |
1.45 |
2.00 |
2.85 |
4.00 |
7.50 |
13.50 |
14.50 |
23.00 |
EMERALD |
5X3mm |
6x4mm |
7x5mm |
8x6mm |
9x7mm |
10x8mm |
12x10 |
16x12 |
18x13 |
20x15 |
| Alexandrite |
0.40 |
0.70 |
1.30 |
2.60 |
3.60 |
4.20 |
8.50 |
14.50 |
22.00 |
27.00 |
| Amethyst |
0.35 |
0.55 |
1.00 |
1.60 |
2.25 |
2.90 |
5.60 |
13.00 |
17.00 |
22.00 |
| Aqua |
0.25 |
0.50 |
0.80 |
1.40 |
2.00 |
3.00 |
4.75 |
13.50 |
17.00 |
22.00 |
| Citrine |
0.35 |
0.55 |
1.00 |
1.60 |
2.25 |
2.90 |
5.60 |
13.00 |
17.00 |
22.00 |
| Diamond |
0.25 |
0.50 |
1.00 |
1.50 |
3.00 |
4.00 |
7.80 |
13.00 |
20.00 |
25.50 |
| Emerald |
0.30 |
0.60 |
0.90 |
1.80 |
2.31 |
3.15 |
5.25 |
14.00 |
17.50 |
22.50 |
| Garnet |
0.40 |
0.80 |
1.20 |
1.70 |
2.50 |
3.50 |
6.35 |
17.50 |
21.00 |
27.00 |
| Peridot |
0.35 |
0.60 |
1.00 |
1.70 |
2.25 |
3.80 |
6.25 |
17.00 |
20.00 |
26.00 |
| Ruby |
0.55 |
0.75 |
1.15 |
1.60 |
2.30 |
2.75 |
6.25 |
12.50 |
18.50 |
27.00 |
| Sapphire |
0.55 |
0.75 |
1.15 |
1.75 |
2.30 |
2.75 |
6.25 |
12.50 |
18.50 |
27.00 |
| Topaz |
0.40 |
0.65 |
1.25 |
2.40 |
3.40 |
4.00 |
8.00 |
14.00 |
21.00 |
26.00 |
| Tourmaline |
0.30 |
0.60 |
1.60 |
2.15 |
2.80 |
3.60 |
5.20 |
13.00 |
16.50 |
25.00 |
| Zircon |
0.60 |
0.85 |
1.70 |
2.35 |
3.90 |
4.50 |
7.00 |
14.30 |
19.90 |
28.70 |
PEAR |
5X3mm |
6x4mm |
8x5mm |
9x6mm |
10x7mm |
13x8mm |