How many carats is a 8 mm diamond?
By HeyGema™ · Updated
In short
A 8 mm round diamond weighs about 1.91 carat (0.38 grams). A 8 mm princess cut weighs about 3.08 carat, and an oval that is 8 mm long about 1 carat.
- 1.91 ctround diamond, 8 mm
- 0.38 gweight
- 0.31 in8 mm in inches
Carat to mm calculator
About 1.91 carat
An estimate for a well-cut stone. A deep or shallow cut faces up smaller or bigger.
8 mm diamond weight by shape
The weight of a well-cut diamond measuring 8 mm. For round and square shapes the number is the diameter or the side. For longer shapes it is the long side, with the width following the usual ratio.
- Round
- Size: 8 mm
- Weight: 1.91 ct
- Oval
- Size: 8 mm x 5.5 mm
- Weight: 1 ct
- Cushion
- Size: 8 mm x 8.0 mm
- Weight: 2.92 ct
- Princess
- Size: 8 mm x 8.0 mm
- Weight: 3.08 ct
- Emerald cut
- Size: 8 mm x 5.7 mm
- Weight: 1.49 ct
- Asscher
- Size: 8 mm x 8.0 mm
- Weight: 3.08 ct
- Radiant
- Size: 8 mm x 6.2 mm
- Weight: 1.86 ct
- Pear
- Size: 8 mm x 5.2 mm
- Weight: 0.83 ct
- Marquise
- Size: 8 mm x 4.0 mm
- Weight: 0.46 ct
- Heart
- Size: 8 mm x 8.0 mm
- Weight: 1.86 ct
- Trillion
- Size: 8 mm x 8.0 mm
- Weight: 1.49 ct
- Baguette
- Size: 8 mm x 4.0 mm
- Weight: 1 ct
8 mm stones in other gems
A round stone of the same size weighs differently in each gem, because gems differ in density.
- Diamond
- Weight of a round stone: 1.91 ct
- Moissanite
- Weight of a round stone: 1.75 ct
- Sapphire
- Weight of a round stone: 2.17 ct
- Ruby
- Weight of a round stone: 2.17 ct
- Emerald
- Weight of a round stone: 1.47 ct
- Aquamarine
- Weight of a round stone: 1.46 ct
- Topaz
- Weight of a round stone: 1.91 ct
- Amethyst
- Weight of a round stone: 1.44 ct
- Spinel
- Weight of a round stone: 1.95 ct
- Tanzanite
- Weight of a round stone: 1.82 ct
- Morganite
- Weight of a round stone: 1.52 ct
8 mm diamond studs
A pair of 8 mm round diamond studs has a total carat weight of about 3.82 carat, 1.91 carat for each stone. See the diamond stud earring size chart.
Nearby sizes
Questions
About 1.91 carat for a well-cut round diamond.
A 8 mm princess cut, measured along one side, weighs about 3.08 carat.
A 8 mm round moissanite is labeled 1.91 carat (diamond equivalent weight) and weighs about 1.75 carat. See the moissanite size chart.
8 mm is 0.31 inches.