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18ct Diamond (Cushion, 15.27×15.27mm, White) vs 18ct Emerald (Cushion, 16.5×16.5mm, Green)


Quick summary: When looked from above (face-up position), 18ct Emerald (16.5×16.5mm, cushion cut) appears 17% larger than 18ct Diamond (15.27×15.27mm, cushion cut). See below how they compare side-by-side on a ring and finger.

18ct Diamond (cushion cut)
vs
18ct Emerald (cushion cut)
white
 
green
15.27×15.27 mm 16.5×16.5 mm
actual size
Actual size of 18ct Diamond (cushion cut, 15.27×15.27mm, White color)   Actual size of 18ct Emerald (cushion cut, 16.5×16.5mm, Green color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
White 18ct Diamond (cushion cut, 15.27×15.27mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Green 18ct Emerald (cushion cut, 16.5×16.5mm) 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
91% vs 98%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 18ct Diamond Cushion (15.27×15.27mm, White) and 18ct Emerald Cushion (16.5×16.5mm, 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.


18 Ct Diamond (Cushion) 18 Ct Emerald (Cushion)
15.27×15.27 mm vs 16.5×16.5 mm
209.86 mm²   245.03 mm²
Face-up size outline for 18ct Emerald (16.5×16.5mm, cushion cut)
Face-up size outline for 18ct Diamond (15.27×15.27mm, cushion cut)
18ct Diamond Cushion (15.27×15.27mm)
18ct Emerald Cushion (16.5×16.5mm)
Difference: 17% (35.17 mm²)
18ct Emerald (Cushion, 16.5×16.5mm) has approx. 17% more face-up area than 18ct Diamond (Cushion, 15.27×15.27mm).


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