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2.5ct Ruby (Round, 8.11×8.11mm, Red) vs 2.5ct Diamond (Emerald, 9.07×6.72mm, White)


Quick summary: When looked from above (face-up position), 2.5ct Diamond (9.07×6.72mm, emerald cut) appears 10% larger than 2.5ct Ruby (8.11×8.11mm, round cut). See below how they compare side-by-side on a ring and finger.

2.5ct Ruby (round cut)
vs
 2.5ct Diamond (emerald cut)
red
 
white
8.11×8.11 mm 9.07×6.72 mm
actual size
Actual size of 2.5ct Ruby (round cut, 8.11×8.11mm, Red color)   Actual size of 2.5ct Diamond (emerald cut, 9.07×6.72mm, White color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Red 2.5ct Ruby (round cut, 8.11×8.11mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
White 2.5ct Diamond (emerald cut, 9.07×6.72mm) 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
 48% vs 40%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 2.5ct Ruby Round (8.11×8.11mm, Red) and 2.5ct Diamond Emerald (9.07×6.72mm, White) 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, Ruby will face-up smaller than Diamond for a given carat weight, because it has higher specific gravity (4 vs. 3.52 - this means it's "heavier" compared to Diamond 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.


2.5 Ct Ruby (Round) 2.5 Ct Diamond (Emerald)
8.11×8.11 mm vs 9.07×6.72 mm
51.66 mm²   56.68 mm²
Face-up size outline for 2.5ct Diamond (9.07×6.72mm, emerald cut)
Face-up size outline for 2.5ct Ruby (8.11×8.11mm, round cut)
2.5ct Ruby Round (8.11×8.11mm)
2.5ct Diamond Emerald (9.07×6.72mm)
Difference: 10% (5.02 mm²)
2.5ct Diamond (Emerald, 9.07×6.72mm) has approx. 10% more face-up area than 2.5ct Ruby (Round, 8.11×8.11mm).


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