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0.42ct Sapphire (Round, 4.48×4.48mm, Blue) vs 2.7ct Diamond (Round, 9.05×9.05mm, White)


Quick summary: When looked from above (face-up position), 2.7ct Diamond (9.05×9.05mm, round cut) appears 4.1 times larger than 0.42ct Sapphire (4.48×4.48mm, round cut). See below how they compare side-by-side on a ring and finger.

0.42ct Sapphire (round cut)
vs
 2.7ct Diamond (round cut)
blue
 
white
4.48×4.48 mm 9.05×9.05 mm
actual size
Actual size of 0.42ct Sapphire (round cut, 4.48×4.48mm, Blue color)   Actual size of 2.7ct Diamond (round cut, 9.05×9.05mm, White color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Blue 0.42ct Sapphire (round cut, 4.48×4.48mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
White 2.7ct Diamond (round cut, 9.05×9.05mm) 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
 27% vs 54%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 0.42ct Sapphire Round (4.48×4.48mm, Blue) and 2.7ct Diamond Round (9.05×9.05mm, 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, Sapphire 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.


0.42 Ct Sapphire (Round) 2.7 Ct Diamond (Round)
4.48×4.48 mm vs 9.05×9.05 mm
15.76 mm²   64.33 mm²
Face-up size outline for 2.7ct Diamond (9.05×9.05mm, round cut)
Face-up size outline for 0.42ct Sapphire (4.48×4.48mm, round cut)
0.42ct Sapphire Round (4.48×4.48mm)
2.7ct Diamond Round (9.05×9.05mm)
Difference: 308% (48.57 mm²)
2.7ct Diamond (Round, 9.05×9.05mm) has approx. 308% more face-up area than 0.42ct Sapphire (Round, 4.48×4.48mm). In other words, it's 4.08x larger.


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