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12.5ct Ruby (Round, 13.87×13.87mm, Red) vs 0.09ct Diamond (Round, 2.91×2.91mm, Red)


Quick summary: When looked from above (face-up position), 12.5ct Ruby (13.87×13.87mm, round cut) appears 22.7 times larger than 0.09ct Diamond (2.91×2.91mm, round cut). See below how they compare side-by-side on a ring and finger.

12.5ct Ruby (round cut)
vs
0.09ct Diamond (round cut)
red
 
red
13.87×13.87 mm 2.91×2.91 mm
actual size
Actual size of 12.5ct Ruby (round cut, 13.87×13.87mm, Red color)   Actual size of 0.09ct Diamond (round cut, 2.91×2.91mm, Red color)
 
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Ring: Skin tone:
Ring width: 3.0 mm
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Left finger image
Ring on left finger
Red 12.5ct Ruby (round cut, 13.87×13.87mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Red 0.09ct Diamond (round cut, 2.91×2.91mm) 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
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Ring diameter: 16.9 mm
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Actual sizes of 12.5ct Ruby Round (13.87×13.87mm, Red) and 0.09ct Diamond Round (2.91×2.91mm, Red) 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.


12.5 Ct Ruby (Round) 0.09 Ct Diamond (Round)
13.87×13.87 mm vs 2.91×2.91 mm
151.09 mm²   6.65 mm²
Face-up size outline for 12.5ct Ruby (13.87×13.87mm, round cut)
Face-up size outline for 0.09ct Diamond (2.91×2.91mm, round cut)
12.5ct Ruby Round (13.87×13.87mm)
0.09ct Diamond Round (2.91×2.91mm)
Difference: 2172% (144.44 mm²)
12.5ct Ruby Round (13.87×13.87mm) has approx. 2172% more face-up area than 0.09ct Diamond Round (2.91×2.91mm). In other words, it's 22.72x larger.


Popular comparisons:

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