How big is a 1.5 carat opal?
By HeyGema™ · Updated
In short
A 1.5 carat round opal measures about 8.8 mm across (0.35 inches), 19% wider than a 1.5 carat diamond (7.4 mm). An oval of the same weight is 10.9 x 7.5 mm and an emerald cut 9.5 x 6.8 mm.
- 8.8 mmround opal, across
- 0.35 inthe same in inches
- 0.30 gweight
- 53%of a size 6 finger's width
Carat to mm calculator
About 8.8 x 8.8 mm
An estimate for a well-cut stone. A deep or shallow cut faces up smaller or bigger.
Round
8.8 mm
Oval
10.9 x 7.5 mm
Cushion
7.6 x 7.6 mm
Princess
7.5 x 7.5 mm
Emerald cut
9.5 x 6.8 mm
Asscher
7.5 x 7.5 mm
Radiant
8.8 x 6.8 mm
Pear
11.6 x 7.5 mm
Marquise
14.1 x 7.1 mm
Heart
8.8 x 8.8 mm
Trillion
9.5 x 9.5 mm
Baguette
10.9 x 5.4 mm
= 5 mm in every picture above
1.5 carat opal size by shape
Face-up measurements of a well-cut 1.5 carat opal. Opal is lighter than diamond (2.10 against 3.52), so the same weight gives a bigger stone, 19% wider across.
- Round
- Length x width: 8.8 mm
- In inches: 0.35 in
- Oval
- Length x width: 10.9 x 7.5 mm
- In inches: 0.43 x 0.29 in
- Cushion
- Length x width: 7.6 x 7.6 mm
- In inches: 0.30 x 0.30 in
- Princess
- Length x width: 7.5 x 7.5 mm
- In inches: 0.29 x 0.29 in
- Emerald cut
- Length x width: 9.5 x 6.8 mm
- In inches: 0.37 x 0.27 in
- Asscher
- Length x width: 7.5 x 7.5 mm
- In inches: 0.29 x 0.29 in
- Radiant
- Length x width: 8.8 x 6.8 mm
- In inches: 0.35 x 0.27 in
- Pear
- Length x width: 11.6 x 7.5 mm
- In inches: 0.46 x 0.29 in
- Marquise
- Length x width: 14.1 x 7.1 mm
- In inches: 0.56 x 0.28 in
- Heart
- Length x width: 8.8 x 8.8 mm
- In inches: 0.35 x 0.35 in
- Trillion
- Length x width: 9.5 x 9.5 mm
- In inches: 0.37 x 0.37 in
- Baguette
- Length x width: 10.9 x 5.4 mm
- In inches: 0.43 x 0.21 in
1.5 carat opal against other gems
- Diamond
- Round, 1.5 carat: 7.4 mm
- Moissanite
- Round, 1.5 carat: 7.6 mm
- Sapphire
- Round, 1.5 carat: 7.1 mm
- Ruby
- Round, 1.5 carat: 7.1 mm
- Emerald
- Round, 1.5 carat: 8.0 mm
- Aquamarine
- Round, 1.5 carat: 8.1 mm
- Morganite
- Round, 1.5 carat: 8.0 mm
- Tanzanite
- Round, 1.5 carat: 7.5 mm
- Opal (this page)
- Round, 1.5 carat: 8.8 mm
1.5 carat opal on a finger
- 4
- Finger width: 14.9 mm
- Round covers: 59%
- Oval covers: 50%
- 5
- Finger width: 15.7 mm
- Round covers: 56%
- Oval covers: 48%
- 6
- Finger width: 16.5 mm
- Round covers: 53%
- Oval covers: 45%
- 7
- Finger width: 17.3 mm
- Round covers: 51%
- Oval covers: 43%
- 8
- Finger width: 18.1 mm
- Round covers: 48%
- Oval covers: 41%
- 9
- Finger width: 18.9 mm
- Round covers: 46%
- Oval covers: 39%
Opal at nearby weights
- 1 carat opal
- Round diameter: 7.7 mm
- 1.5 ct (this page)
- Round diameter: 8.8 mm
- 2 carat opal
- Round diameter: 9.7 mm
Questions
A round 1.5 carat opal is about 8.8 mm across. Other shapes are longer than they are wide: an oval is 10.9 x 7.5 mm.
Yes. A round 1.5 carat opal is 19% wider than a 1.5 carat diamond (7.4 mm).
0.30 grams. A carat is 200 milligrams for every gem.
A round 1.5 carat opal covers 53% of the width of a size 6 finger. Compare it with a ring you have tried on in the finger chart above.