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3ct Spinel (Round, 8.93×8.93mm, Red) vs 3ct Alexandrite (Round, 8.83×8.83mm, Bluish Green)


Quick summary: When looked from above (face-up position), 3ct Spinel (8.93×8.93mm, round cut) appears 2% larger than 3ct Alexandrite (8.83×8.83mm, round cut). See below how they compare side-by-side on a ring and finger.

3ct Spinel (round cut)
vs
3ct Alexandrite (round cut)
red
 
bluish green
8.93×8.93 mm 8.83×8.83 mm
actual size
Actual size of 3ct Spinel (round cut, 8.93×8.93mm, Red color)   Actual size of 3ct Alexandrite (round cut, 8.83×8.83mm, Bluish Green color)
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Red 3ct Spinel (round cut, 8.93×8.93mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Bluish Green 3ct Alexandrite (round cut, 8.83×8.83mm) 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
53% vs 53%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 3ct Spinel Round (8.93×8.93mm, Red) and 3ct Alexandrite Round (8.83×8.83mm, Bluish 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, Alexandrite will face-up smaller than Spinel for a given carat weight, because it has higher specific gravity (3.73 vs. 3.6 - this means it's "heavier" compared to Spinel 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.


3 Ct Spinel (Round) 3 Ct Alexandrite (Round)
8.93×8.93 mm vs 8.83×8.83 mm
62.63 mm²   61.24 mm²
Face-up size outline for 3ct Spinel (8.93×8.93mm, round cut)
Face-up size outline for 3ct Alexandrite (8.83×8.83mm, round cut)
3ct Spinel Round (8.93×8.93mm)
3ct Alexandrite Round (8.83×8.83mm)
Difference: 2% (1.39 mm²)
3ct Spinel (Round, 8.93×8.93mm) has approx. 2% more face-up area than 3ct Alexandrite (Round, 8.83×8.83mm).


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