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20ct Sapphire (Round, 16.23×16.23mm, Blue) vs 1.2ct Diamond (Round, 6.91×6.91mm, White)


Quick summary: When looked from above (face-up position), 20ct Sapphire (16.23×16.23mm, round cut) appears 5.5 times larger than 1.2ct Diamond (6.91×6.91mm, round cut). See below how they compare side-by-side on a ring and finger.

20ct Sapphire (round cut)
vs
 1.2ct Diamond (round cut)
blue
 
white
16.23×16.23 mm 6.91×6.91 mm
actual size
Actual size of 20ct Sapphire (round cut, 16.23×16.23mm, Blue color)   Actual size of 1.2ct Diamond (round cut, 6.91×6.91mm, White color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Blue 20ct Sapphire (round cut, 16.23×16.23mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
White 1.2ct Diamond (round cut, 6.91×6.91mm) 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
Finger coverage
 97% vs 41%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 20ct Sapphire Round (16.23×16.23mm, Blue) and 1.2ct Diamond Round (6.91×6.91mm, 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.


20 Ct Sapphire (Round) 1.2 Ct Diamond (Round)
16.23×16.23 mm vs 6.91×6.91 mm
206.88 mm²   37.5 mm²
Face-up size outline for 20ct Sapphire (16.23×16.23mm, round cut)
Face-up size outline for 1.2ct Diamond (6.91×6.91mm, round cut)
20ct Sapphire Round (16.23×16.23mm)
1.2ct Diamond Round (6.91×6.91mm)
Difference: 452% (169.38 mm²)
20ct Sapphire (Round, 16.23×16.23mm) has approx. 452% more face-up area than 1.2ct Diamond (Round, 6.91×6.91mm). In other words, it's 5.52x larger.


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