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12ct Benitoite (Trillion, 17.25×17.25mm, Blue) vs 12ct Alexandrite (Trillion, 17.13×17.13mm, Bluish Green)


Quick summary: When looked from above (face-up position), 12ct Benitoite (17.25×17.25mm, trillion cut) appears 1% larger than 12ct Alexandrite (17.13×17.13mm, trillion cut). See below how they compare side-by-side on a ring and finger.

12ct Benitoite (trillion cut)
vs
 12ct Alexandrite (trillion cut)
blue
 
bluish green
17.25×17.25 mm 17.13×17.13 mm
actual size
Actual size of 12ct Benitoite (trillion cut, 17.25×17.25mm, Blue color)   Actual size of 12ct Alexandrite (trillion cut, 17.13×17.13mm, Bluish Green color)
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Blue 12ct Benitoite (trillion cut, 17.25×17.25mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Bluish Green 12ct Alexandrite (trillion cut, 17.13×17.13mm) 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
 103% vs 102%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 12ct Benitoite Trillion (17.25×17.25mm, Blue) and 12ct Alexandrite Trillion (17.13×17.13mm, 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 slightly smaller than Benitoite for a given carat weight, because it has higher specific gravity (3.73 vs. 3.65 - this means it's "slightly heavier" compared to Benitoite 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.


12 Ct Benitoite (Trillion) 12 Ct Alexandrite (Trillion)
17.25×17.25 mm vs 17.13×17.13 mm
184.49 mm²   181.93 mm²
Face-up size outline for 12ct Benitoite (17.25×17.25mm, trillion cut)
Face-up size outline for 12ct Alexandrite (17.13×17.13mm, trillion cut)
12ct Benitoite Trillion (17.25×17.25mm)
12ct Alexandrite Trillion (17.13×17.13mm)
Difference: 1% (2.56 mm²)
12ct Benitoite (Trillion, 17.25×17.25mm) has approx. 1% more face-up area than 12ct Alexandrite (Trillion, 17.13×17.13mm).


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