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2.4ct Sapphire (Round, 8×8mm, Blue) vs 3ct Alexandrite (Round, 8.85×8.85mm, Purple)


Quick summary: When looked from above (face-up position), 3ct Alexandrite (8.85×8.85mm, round cut) appears 22% larger than 2.4ct Sapphire (8×8mm, round cut). See below how they compare side-by-side on a ring and finger.

2.4ct Sapphire (round cut)
vs
 3ct Alexandrite (round cut)
blue
 
purple
8×8 mm 8.85×8.85 mm
actual size
Actual size of 2.4ct Sapphire (round cut, 8×8mm, Blue color)   Actual size of 3ct Alexandrite (round cut, 8.85×8.85mm, Purple color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Blue 2.4ct Sapphire (round cut, 8×8mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Purple 3ct Alexandrite (round cut, 8.85×8.85mm) 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
 48% vs 53%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 2.4ct Sapphire Round (8×8mm, Blue) and 3ct Alexandrite Round (8.85×8.85mm, Purple) 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 Alexandrite for a given carat weight, because it has higher specific gravity (4 vs. 3.73 - this means it's "heavier" compared to Alexandrite 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.


2.4 Ct Sapphire (Round) 3 Ct Alexandrite (Round)
8×8 mm vs 8.85×8.85 mm
50.27 mm²   61.51 mm²
Face-up size outline for 3ct Alexandrite (8.85×8.85mm, round cut)
Face-up size outline for 2.4ct Sapphire (8×8mm, round cut)
2.4ct Sapphire Round (8×8mm)
3ct Alexandrite Round (8.85×8.85mm)
Difference: 22% (11.24 mm²)
3ct Alexandrite (Round, 8.85×8.85mm) has approx. 22% more face-up area than 2.4ct Sapphire (Round, 8×8mm).


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