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20ct Sapphire (Cabochon, 18.57×12.38mm, Blue) vs 20ct Ruby (Oval, 20.81×13.87mm, Red)


Quick summary: When looked from above (face-up position), 20ct Ruby (20.81×13.87mm, oval cut) appears 26% larger than 20ct Sapphire (18.57×12.38mm, cabochon cut). See below how they compare side-by-side on a ring and finger.

20ct Sapphire (cabochon cut)
vs
 20ct Ruby (oval cut)
blue
 
red
18.57×12.38 mm 20.81×13.87 mm
actual size
Actual size of 20ct Sapphire (cabochon cut, 18.57×12.38mm, Blue color)   Actual size of 20ct Ruby (oval cut, 20.81×13.87mm, Red 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 (cabochon cut, 18.57×12.38mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Red 20ct Ruby (oval cut, 20.81×13.87mm) 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
 74% vs 83%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 20ct Sapphire Cabochon (18.57×12.38mm, Blue) and 20ct Ruby Oval (20.81×13.87mm, 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

Sapphire and Ruby have the same specific gravity so their face-up size depends on the weight, shape and 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 (Cabochon) 20 Ct Ruby (Oval)
18.57×12.38 mm vs 20.81×13.87 mm
188.52 mm²   236.68 mm²
Face-up size outline for 20ct Ruby (20.81×13.87mm, oval cut)
Face-up size outline for 20ct Sapphire (18.57×12.38mm, cabochon cut)
20ct Sapphire Cabochon (18.57×12.38mm)
20ct Ruby Oval (20.81×13.87mm)
Difference: 26% (48.16 mm²)
20ct Ruby (Oval, 20.81×13.87mm) has approx. 26% more face-up area than 20ct Sapphire (Cabochon, 18.57×12.38mm).


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