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40ct Benitoite (Cabochon, 24.14×16.09mm, Blue) vs 40ct Alexandrite (Cabochon, 23.96×15.97mm, Bluish Green)


Quick summary: When looked from above (face-up position), 40ct Benitoite (24.14×16.09mm, cabochon cut) appears 2% larger than 40ct Alexandrite (23.96×15.97mm, cabochon cut). See below how they compare side-by-side on a ring and finger.

40ct Benitoite (cabochon cut)
vs
40ct Alexandrite (cabochon cut)
blue
 
bluish green
24.14×16.09 mm 23.96×15.97 mm
actual size
Actual size of 40ct Benitoite (cabochon cut, 24.14×16.09mm, Blue color)   Actual size of 40ct Alexandrite (cabochon cut, 23.96×15.97mm, 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 40ct Benitoite (cabochon cut, 24.14×16.09mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Bluish Green 40ct Alexandrite (cabochon cut, 23.96×15.97mm) 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
96% vs 95%
Saved...
Ring diameter: 16.9 mm
USA UK Asia EU1 EU2
Actual sizes of 40ct Benitoite Cabochon (24.14×16.09mm, Blue) and 40ct Alexandrite Cabochon (23.96×15.97mm, 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.


40 Ct Benitoite (Cabochon) 40 Ct Alexandrite (Cabochon)
24.14×16.09 mm vs 23.96×15.97 mm
318.5 mm²   313.77 mm²
Face-up size outline for 40ct Benitoite (24.14×16.09mm, cabochon cut)
Face-up size outline for 40ct Alexandrite (23.96×15.97mm, cabochon cut)
40ct Benitoite Cabochon (24.14×16.09mm)
40ct Alexandrite Cabochon (23.96×15.97mm)
Difference: 2% (4.73 mm²)
40ct Benitoite (Cabochon, 24.14×16.09mm) has approx. 2% more face-up area than 40ct Alexandrite (Cabochon, 23.96×15.97mm).


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