How big are 0.4 carat diamond stud earrings?
By HeyGema™ · Updated
In short
0.4 carat diamond stud earrings (ctw) are two stones of 0.2 carat. A round stone of 0.2 carat is about 3.8 mm across, a princess 3.2 x 3.2 mm and a cushion 3.3 x 3.3 mm.
- 0.2 cteach stone
- 3.8 mmround, across
- 0.15 inthe same in inches
Carat to mm calculator
About 3.8 x 3.8 mm
An estimate for a well-cut stone. A deep or shallow cut faces up smaller or bigger.
Round
3.8 mm
Princess
3.2 x 3.2 mm
Cushion
3.3 x 3.3 mm
Oval
4.7 x 3.2 mm
Pear
5.0 x 3.2 mm
Heart
3.8 x 3.8 mm
= 1 mm in every picture above
0.4 carat total weight stud earrings in mm
A pair of 0.4 ctw diamond studs has two stones of 0.2 carat each. A round stone of that weight measures about 3.8 mm (0.15 in) across the face. Each weighs 0.040 grams.
- Round
- Size of each stone: 3.8 mm
- In inches: 0.15 in
- Princess
- Size of each stone: 3.2 x 3.2 mm
- In inches: 0.13 x 0.13 in
- Cushion
- Size of each stone: 3.3 x 3.3 mm
- In inches: 0.13 x 0.13 in
- Oval
- Size of each stone: 4.7 x 3.2 mm
- In inches: 0.18 x 0.13 in
- Pear
- Size of each stone: 5.0 x 3.2 mm
- In inches: 0.20 x 0.13 in
- Heart
- Size of each stone: 3.8 x 3.8 mm
- In inches: 0.15 x 0.15 in
0.4 ctw studs next to a coin
0.2 ct diamond
3.8 mm
US dime
17.9 mm
US nickel
21.2 mm
US quarter
24.3 mm
Nearby stud sizes
- 0.33 ctw
- Each stone: 0.165 ct
- Round size: 3.5 mm
- 0.4 ctw (this page)
- Each stone: 0.2 ct
- Round size: 3.8 mm
- 0.5 ctw
- Each stone: 0.25 ct
- Round size: 4.1 mm
How to compare studs from different sellers
Ask for the size in mm of each stone along with the total weight. Two pairs of the same ctw can differ by a few tenths of a millimeter because of the cut. See the stud earring size chart for every weight, or how to measure a diamond you already own.
Questions
Each round stone of a 0.4 ctw pair is about 3.8 mm across (0.15 in).
Two. ctw is the combined weight of the pair, so each stone is 0.2 carat.
Each stone is 3.8 mm across, 21% of the width of a US dime (17.91 mm). Round 0.2 carat stones are the same size whether they sit in a ring or an earring.
0.2 carat each.