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1.8ct Ruby (Oval, 9.2×6.13mm, Red) vs 1ct Diamond (Oval, 8.12×5.41mm, White)


Quick summary: When looked from above (face-up position), 1.8ct Ruby (9.2×6.13mm, oval cut) appears 28% larger than 1ct Diamond (8.12×5.41mm, oval cut). See below how they compare side-by-side on a ring and finger.

1.8ct Ruby (oval cut)
vs
 1ct Diamond (oval cut)
red
 
white
9.2×6.13 mm 8.12×5.41 mm
actual size
Actual size of 1.8ct Ruby (oval cut, 9.2×6.13mm, Red color)   Actual size of 1ct Diamond (oval cut, 8.12×5.41mm, White color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Red 1.8ct Ruby (oval cut, 9.2×6.13mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
White 1ct Diamond (oval cut, 8.12×5.41mm) 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
 37% vs 33%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 1.8ct Ruby Oval (9.2×6.13mm, Red) and 1ct Diamond Oval (8.12×5.41mm, 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.


1.8 Ct Ruby (Oval) 1 Ct Diamond (Oval)
9.2×6.13 mm vs 8.12×5.41 mm
46.24 mm²   36.02 mm²
Face-up size outline for 1.8ct Ruby (9.2×6.13mm, oval cut)
Face-up size outline for 1ct Diamond (8.12×5.41mm, oval cut)
1.8ct Ruby Oval (9.2×6.13mm)
1ct Diamond Oval (8.12×5.41mm)
Difference: 28% (10.22 mm²)
1.8ct Ruby (Oval, 9.2×6.13mm) has approx. 28% more face-up area than 1ct Diamond (Oval, 8.12×5.41mm).


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