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3ct Spinel (Trillion, 10.92×10.92mm, Red) vs 3ct Alexandrite (Trillion, 10.79×10.79mm, Bluish Green)


Quick summary: When looked from above (face-up position), 3ct Spinel (10.92×10.92mm, trillion cut) appears 2% larger than 3ct Alexandrite (10.79×10.79mm, trillion cut). See below how they compare side-by-side on a ring and finger.

3ct Spinel (trillion cut)
vs
 3ct Alexandrite (trillion cut)
red
 
bluish green
10.92×10.92 mm 10.79×10.79 mm
actual size
Actual size of 3ct Spinel (trillion cut, 10.92×10.92mm, Red color)   Actual size of 3ct Alexandrite (trillion cut, 10.79×10.79mm, 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 (trillion cut, 10.92×10.92mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Bluish Green 3ct Alexandrite (trillion cut, 10.79×10.79mm) 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
 65% vs 64%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 3ct Spinel Trillion (10.92×10.92mm, Red) and 3ct Alexandrite Trillion (10.79×10.79mm, 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 (Trillion) 3 Ct Alexandrite (Trillion)
10.92×10.92 mm vs 10.79×10.79 mm
73.93 mm²   72.18 mm²
Face-up size outline for 3ct Spinel (10.92×10.92mm, trillion cut)
Face-up size outline for 3ct Alexandrite (10.79×10.79mm, trillion cut)
3ct Spinel Trillion (10.92×10.92mm)
3ct Alexandrite Trillion (10.79×10.79mm)
Difference: 2% (1.75 mm²)
3ct Spinel (Trillion, 10.92×10.92mm) has approx. 2% more face-up area than 3ct Alexandrite (Trillion, 10.79×10.79mm).


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