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0.3ct Emerald (Round, 4.56×4.56mm, Green) vs 0.4ct Diamond (Round, 4.79×4.79mm, Bluish Green)


Quick summary: When looked from above (face-up position), 0.4ct Colored Diamond (4.79×4.79mm, round cut) appears 10% larger than 0.3ct Emerald (4.56×4.56mm, round cut). See below how they compare side-by-side on a ring and finger.

0.3ct Emerald (round cut)
vs
 0.4ct Diamond (round cut)
green
 
bluish green
4.56×4.56 mm 4.79×4.79 mm
actual size
Actual size of 0.3ct Emerald (round cut, 4.56×4.56mm, Green color)   Actual size of 0.4ct Diamond (round cut, 4.79×4.79mm, Bluish Green color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Green 0.3ct Emerald (round cut, 4.56×4.56mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Bluish Green 0.4ct Diamond (round cut, 4.79×4.79mm) on a right ring and finger
Your settings
Ring
 Gold
Skin tone
 Light
Ring diameter
 16.9 mm
Ring width
 3.0 mm
Finger length
 64 mm
Finger coverage
 27% vs 29%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 0.3ct Emerald Round (4.56×4.56mm, Green) and 0.4ct Diamond Round (4.79×4.79mm, Bluish Green) as they would appear on a ring and finger. Adjust the ring and finger size to get an idea of how these gemstones would look on your finger.

Where to buy?

For certified gemstones, high-end gemstone jewelry, and birthstone jewelry, see Blue Nile

Face-up Size

All things being equal, Diamond will face-up smaller than Emerald for a given carat weight, because it has higher specific gravity (3.52 vs. 2.72 - this means it's "heavier" compared to Emerald of the same size). Face-up size also depends heavily on the proportions of the cut.

Face-up area is a measure of the size of the gem when viewed from above (as set in a ring). It tells you how big the gem is at the girdle plane.


0.3 Ct Emerald (Round) 0.4 Ct Colored Diamond (Round)
4.56×4.56 mm vs 4.79×4.79 mm
16.33 mm²   18.02 mm²
Face-up size outline for 0.4ct Diamond (4.79×4.79mm, round cut)
Face-up size outline for 0.3ct Emerald (4.56×4.56mm, round cut)
0.3ct Emerald Round (4.56×4.56mm)
0.4ct Colored Diamond Round (4.79×4.79mm)
Difference: 10% (1.69 mm²)
0.4ct Colored Diamond (Round, 4.79×4.79mm) has approx. 10% more face-up area than 0.3ct Emerald (Round, 4.56×4.56mm).


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