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9ct Spinel (Round, 12.88×12.88mm, Red) vs 9ct Alexandrite (Round, 12.73×12.73mm, Bluish Green)


Quick summary: When looked from above (face-up position), 9ct Spinel (12.88×12.88mm, round cut) appears 2% larger than 9ct Alexandrite (12.73×12.73mm, round cut). See below how they compare side-by-side on a ring and finger.

9ct Spinel (round cut)
vs
 9ct Alexandrite (round cut)
red
 
bluish green
12.88×12.88 mm 12.73×12.73 mm
actual size
Actual size of 9ct Spinel (round cut, 12.88×12.88mm, Red color)   Actual size of 9ct Alexandrite (round cut, 12.73×12.73mm, 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 9ct Spinel (round cut, 12.88×12.88mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Bluish Green 9ct Alexandrite (round cut, 12.73×12.73mm) 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
 77% vs 76%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 9ct Spinel Round (12.88×12.88mm, Red) and 9ct Alexandrite Round (12.73×12.73mm, 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.


9 Ct Spinel (Round) 9 Ct Alexandrite (Round)
12.88×12.88 mm vs 12.73×12.73 mm
130.29 mm²   127.28 mm²
Face-up size outline for 9ct Spinel (12.88×12.88mm, round cut)
Face-up size outline for 9ct Alexandrite (12.73×12.73mm, round cut)
9ct Spinel Round (12.88×12.88mm)
9ct Alexandrite Round (12.73×12.73mm)
Difference: 2% (3.01 mm²)
9ct Spinel (Round, 12.88×12.88mm) has approx. 2% more face-up area than 9ct Alexandrite (Round, 12.73×12.73mm).


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