How big is a 1 carat topaz?
By HeyGema™ · Updated
In short
A 1 carat round topaz measures about 6.4 mm across (0.25 inches), about the same width as a diamond of the same weight. An oval of the same weight is 8.0 x 5.5 mm and an emerald cut 7.0 x 5.0 mm.
- 6.4 mmround topaz, across
- 0.25 inthe same in inches
- 0.20 gweight
- 39%of a size 6 finger's width
Carat to mm calculator
About 6.4 x 6.4 mm
An estimate for a well-cut stone. A deep or shallow cut faces up smaller or bigger.
Round
6.4 mm
Oval
8.0 x 5.5 mm
Cushion
5.6 x 5.6 mm
Princess
5.5 x 5.5 mm
Emerald cut
7.0 x 5.0 mm
Asscher
5.5 x 5.5 mm
Radiant
6.5 x 5.0 mm
Pear
8.5 x 5.5 mm
Marquise
10.4 x 5.2 mm
Heart
6.5 x 6.5 mm
Trillion
7.0 x 7.0 mm
Baguette
8.0 x 4.0 mm
= 2 mm in every picture above
1 carat topaz size by shape
Face-up measurements of a well-cut 1 carat topaz. Topaz has about the same density as diamond (3.53 against 3.52), so the same weight gives the same size.
- Round
- Length x width: 6.4 mm
- In inches: 0.25 in
- Oval
- Length x width: 8.0 x 5.5 mm
- In inches: 0.31 x 0.22 in
- Cushion
- Length x width: 5.6 x 5.6 mm
- In inches: 0.22 x 0.22 in
- Princess
- Length x width: 5.5 x 5.5 mm
- In inches: 0.22 x 0.22 in
- Emerald cut
- Length x width: 7.0 x 5.0 mm
- In inches: 0.28 x 0.20 in
- Asscher
- Length x width: 5.5 x 5.5 mm
- In inches: 0.22 x 0.22 in
- Radiant
- Length x width: 6.5 x 5.0 mm
- In inches: 0.26 x 0.20 in
- Pear
- Length x width: 8.5 x 5.5 mm
- In inches: 0.33 x 0.22 in
- Marquise
- Length x width: 10.4 x 5.2 mm
- In inches: 0.41 x 0.20 in
- Heart
- Length x width: 6.5 x 6.5 mm
- In inches: 0.26 x 0.26 in
- Trillion
- Length x width: 7.0 x 7.0 mm
- In inches: 0.28 x 0.28 in
- Baguette
- Length x width: 8.0 x 4.0 mm
- In inches: 0.31 x 0.16 in
1 carat topaz against other gems
- Diamond
- Round, 1 carat: 6.5 mm
- Moissanite
- Round, 1 carat: 6.6 mm
- Sapphire
- Round, 1 carat: 6.2 mm
- Ruby
- Round, 1 carat: 6.2 mm
- Emerald
- Round, 1 carat: 7.0 mm
- Aquamarine
- Round, 1 carat: 7.0 mm
- Morganite
- Round, 1 carat: 7.0 mm
- Tanzanite
- Round, 1 carat: 6.6 mm
- Topaz (this page)
- Round, 1 carat: 6.4 mm
1 carat topaz on a finger
- 4
- Finger width: 14.9 mm
- Round covers: 43%
- Oval covers: 37%
- 5
- Finger width: 15.7 mm
- Round covers: 41%
- Oval covers: 35%
- 6
- Finger width: 16.5 mm
- Round covers: 39%
- Oval covers: 33%
- 7
- Finger width: 17.3 mm
- Round covers: 37%
- Oval covers: 32%
- 8
- Finger width: 18.1 mm
- Round covers: 36%
- Oval covers: 30%
- 9
- Finger width: 18.9 mm
- Round covers: 34%
- Oval covers: 29%
Topaz at nearby weights
- 0.5 carat topaz
- Round diameter: 5.1 mm
- 1 ct (this page)
- Round diameter: 6.4 mm
- 1.5 carat topaz
- Round diameter: 7.4 mm
Questions
A round 1 carat topaz is about 6.4 mm across. Other shapes are longer than they are wide: an oval is 8.0 x 5.5 mm.
About the same. A round 1 carat topaz is about the same width as a diamond of the same weight.
0.20 grams. A carat is 200 milligrams for every gem.
A round 1 carat topaz covers 39% of the width of a size 6 finger. Compare it with a ring you have tried on in the finger chart above.