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1.9ct Ruby (Round, 7.4×7.4mm, Red) vs 1.5ct Diamond (Round, 7.44×7.44mm, White)


Quick summary: When looked from above (face-up position), 1.5ct Diamond (7.44×7.44mm, round cut) appears 1% larger than 1.9ct Ruby (7.4×7.4mm, round cut). See below how they compare side-by-side on a ring and finger.

1.9ct Ruby (round cut)
vs
 1.5ct Diamond (round cut)
red
 
white
7.4×7.4 mm 7.44×7.44 mm
actual size
Actual size of 1.9ct Ruby (round cut, 7.4×7.4mm, Red color)   Actual size of 1.5ct Diamond (round cut, 7.44×7.44mm, White color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Red 1.9ct Ruby (round cut, 7.4×7.4mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
White 1.5ct Diamond (round cut, 7.44×7.44mm) 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
 44% vs 45%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 1.9ct Ruby Round (7.4×7.4mm, Red) and 1.5ct Diamond Round (7.44×7.44mm, 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.


1.9 Ct Ruby (Round) 1.5 Ct Diamond (Round)
7.4×7.4 mm vs 7.44×7.44 mm
43.01 mm²   43.47 mm²
Face-up size outline for 1.5ct Diamond (7.44×7.44mm, round cut)
Face-up size outline for 1.9ct Ruby (7.4×7.4mm, round cut)
1.9ct Ruby Round (7.4×7.4mm)
1.5ct Diamond Round (7.44×7.44mm)
Difference: 1% (0.46 mm²)
1.5ct Diamond (Round, 7.44×7.44mm) has approx. 1% more face-up area than 1.9ct Ruby (Round, 7.4×7.4mm).


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