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20ct Amethyst (Round, 18.62×18.62mm, Violet) vs 8ct Emerald (Emerald, 14.55×10.78mm, Green)


Quick summary: When looked from above (face-up position), 20ct Amethyst (18.62×18.62mm, round cut) appears 87% larger than 8ct Emerald (14.55×10.78mm, emerald cut). See below how they compare side-by-side on a ring and finger.

20ct Amethyst (round cut)
vs
 8ct Emerald (emerald cut)
violet
 
green
18.62×18.62 mm 14.55×10.78 mm
actual size
Actual size of 20ct Amethyst (round cut, 18.62×18.62mm, Violet color)   Actual size of 8ct Emerald (emerald cut, 14.55×10.78mm, Green color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Violet 20ct Amethyst (round cut, 18.62×18.62mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Green 8ct Emerald (emerald cut, 14.55×10.78mm) 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
 111% vs 64%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 20ct Amethyst Round (18.62×18.62mm, Violet) and 8ct Emerald Emerald (14.55×10.78mm, Green) 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, Emerald will face-up slightly smaller than Amethyst for a given carat weight, because it has higher specific gravity (2.72 vs. 2.65 - this means it's "slightly heavier" compared to Amethyst 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 Amethyst (Round) 8 Ct Emerald (Emerald)
18.62×18.62 mm vs 14.55×10.78 mm
272.3 mm²   145.87 mm²
Face-up size outline for 20ct Amethyst (18.62×18.62mm, round cut)
Face-up size outline for 8ct Emerald (14.55×10.78mm, emerald cut)
20ct Amethyst Round (18.62×18.62mm)
8ct Emerald Emerald (14.55×10.78mm)
Difference: 87% (126.43 mm²)
20ct Amethyst (Round, 18.62×18.62mm) has approx. 87% more face-up area than 8ct Emerald (Emerald, 14.55×10.78mm).


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