×
carat vs. color  length*  width*
  ×

(or examine a )
* size in mm (optional)

28ct Amethyst (Radiant, 19.19×19.19mm, Violet) vs 28ct Alexandrite (Radiant, 17.12×17.12mm, Bluish Green)


Quick summary: When looked from above (face-up position), 28ct Amethyst (19.19×19.19mm, radiant cut) appears 26% larger than 28ct Alexandrite (17.12×17.12mm, radiant cut). See below how they compare side-by-side on a ring and finger.

28ct Amethyst (radiant cut)
vs
28ct Alexandrite (radiant cut)
violet
 
bluish green
19.19×19.19 mm 17.12×17.12 mm
actual size
Actual size of 28ct Amethyst (radiant cut, 19.19×19.19mm, Violet color)   Actual size of 28ct Alexandrite (radiant cut, 17.12×17.12mm, Bluish Green color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Violet 28ct Amethyst (radiant cut, 19.19×19.19mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Bluish Green 28ct Alexandrite (radiant cut, 17.12×17.12mm) 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
114% vs 102%
Saved...
Ring diameter: 16.9 mm
USA UK Asia EU1 EU2
Actual sizes of 28ct Amethyst Radiant (19.19×19.19mm, Violet) and 28ct Alexandrite Radiant (17.12×17.12mm, 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 Amethyst for a given carat weight, because it has higher specific gravity (3.73 vs. 2.65 - this means it's "heavier" compared to Amethyst 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.


28 Ct Amethyst (Radiant) 28 Ct Alexandrite (Radiant)
19.19×19.19 mm vs 17.12×17.12 mm
349.84 mm²   278.44 mm²
Face-up size outline for 28ct Amethyst (19.19×19.19mm, radiant cut)
Face-up size outline for 28ct Alexandrite (17.12×17.12mm, radiant cut)
28ct Amethyst Radiant (19.19×19.19mm)
28ct Alexandrite Radiant (17.12×17.12mm)
Difference: 26% (71.4 mm²)
28ct Amethyst (Radiant, 19.19×19.19mm) has approx. 26% more face-up area than 28ct Alexandrite (Radiant, 17.12×17.12mm).


Popular comparisons: