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2.51ct Sapphire (Emerald, 8.35×6.4mm, Blue) vs 8.23ct Amethyst (Oval, 15.9×12.7mm, Light Violet)


Quick summary: When looked from above (face-up position), 8.23ct Amethyst (15.9×12.7mm, oval cut) appears 3.3 times larger than 2.51ct Sapphire (8.35×6.4mm, emerald cut). See below how they compare side-by-side on a ring and finger.

2.51ct Sapphire (emerald cut)
vs
 8.23ct Amethyst (oval cut)
blue
 
light violet
8.35×6.4 mm 15.9×12.7 mm
actual size
Actual size of 2.51ct Sapphire (emerald cut, 8.35×6.4mm, Blue color)   Actual size of 8.23ct Amethyst (oval cut, 15.9×12.7mm, Light Violet color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Blue 2.51ct Sapphire (emerald cut, 8.35×6.4mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Light Violet 8.23ct Amethyst (oval cut, 15.9×12.7mm) 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
 38% vs 76%
Saved...
Ring diameter: 16.9 mm
USA UK Asia EU1 EU2
Actual sizes of 2.51ct Sapphire Emerald (8.35×6.4mm, Blue) and 8.23ct Amethyst Oval (15.9×12.7mm, Light Violet) 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 Amethyst for a given carat weight, because it has higher specific gravity (4 vs. 2.65 - this means it's "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.


2.51 Ct Sapphire (Emerald) 8.23 Ct Amethyst (Oval)
8.35×6.4 mm vs 15.9×12.7 mm
49.7 mm²   165.58 mm²
Face-up size outline for 8.23ct Amethyst (15.9×12.7mm, oval cut)
Face-up size outline for 2.51ct Sapphire (8.35×6.4mm, emerald cut)
2.51ct Sapphire Emerald (8.35×6.4mm)
8.23ct Amethyst Oval (15.9×12.7mm)
Difference: 233% (115.88 mm²)
8.23ct Amethyst (Oval, 15.9×12.7mm) has approx. 233% more face-up area than 2.51ct Sapphire (Emerald, 8.35×6.4mm). In other words, it's 3.33x larger.


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