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15ct Alexandrite (Cushion, 13.97×13.97mm, Bluish Green) vs 15ct Topaz (Cushion, 14.23×14.23mm, Blue)


Quick summary: When looked from above (face-up position), 15ct Topaz (14.23×14.23mm, cushion cut) appears 4% larger than 15ct Alexandrite (13.97×13.97mm, cushion cut). See below how they compare side-by-side on a ring and finger.

15ct Alexandrite (cushion cut)
vs
15ct Topaz (cushion cut)
bluish green
 
blue
13.97×13.97 mm 14.23×14.23 mm
actual size
Actual size of 15ct Alexandrite (cushion cut, 13.97×13.97mm, Bluish Green color)   Actual size of 15ct Topaz (cushion cut, 14.23×14.23mm, Blue color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Bluish Green 15ct Alexandrite (cushion cut, 13.97×13.97mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Blue 15ct Topaz (cushion cut, 14.23×14.23mm) 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
83% vs 85%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 15ct Alexandrite Cushion (13.97×13.97mm, Bluish Green) and 15ct Topaz Cushion (14.23×14.23mm, Blue) 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 Topaz for a given carat weight, because it has higher specific gravity (3.73 vs. 3.53 - this means it's "heavier" compared to Topaz 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.


15 Ct Alexandrite (Cushion) 15 Ct Topaz (Cushion)
13.97×13.97 mm vs 14.23×14.23 mm
175.64 mm²   182.24 mm²
Face-up size outline for 15ct Topaz (14.23×14.23mm, cushion cut)
Face-up size outline for 15ct Alexandrite (13.97×13.97mm, cushion cut)
15ct Alexandrite Cushion (13.97×13.97mm)
15ct Topaz Cushion (14.23×14.23mm)
Difference: 4% (6.6 mm²)
15ct Topaz (Cushion, 14.23×14.23mm) has approx. 4% more face-up area than 15ct Alexandrite (Cushion, 13.97×13.97mm).


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