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12ct Amethyst (Marquise, 25.54×12.77mm, Violet) vs 12ct Alexandrite (Marquise, 22.78×11.39mm, Bluish Green)


Quick summary: When looked from above (face-up position), 12ct Amethyst (25.54×12.77mm, marquise cut) appears 26% larger than 12ct Alexandrite (22.78×11.39mm, marquise cut). See below how they compare side-by-side on a ring and finger.

12ct Amethyst (marquise cut)
vs
 12ct Alexandrite (marquise cut)
violet
 
bluish green
25.54×12.77 mm 22.78×11.39 mm
actual size
Actual size of 12ct Amethyst (marquise cut, 25.54×12.77mm, Violet color)   Actual size of 12ct Alexandrite (marquise cut, 22.78×11.39mm, 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 12ct Amethyst (marquise cut, 25.54×12.77mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Bluish Green 12ct Alexandrite (marquise cut, 22.78×11.39mm) 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
 76% vs 68%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 12ct Amethyst Marquise (25.54×12.77mm, Violet) and 12ct Alexandrite Marquise (22.78×11.39mm, 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.


12 Ct Amethyst (Marquise) 12 Ct Alexandrite (Marquise)
25.54×12.77 mm vs 22.78×11.39 mm
231.56 mm²   184.22 mm²
Face-up size outline for 12ct Amethyst (25.54×12.77mm, marquise cut)
Face-up size outline for 12ct Alexandrite (22.78×11.39mm, marquise cut)
12ct Amethyst Marquise (25.54×12.77mm)
12ct Alexandrite Marquise (22.78×11.39mm)
Difference: 26% (47.34 mm²)
12ct Amethyst (Marquise, 25.54×12.77mm) has approx. 26% more face-up area than 12ct Alexandrite (Marquise, 22.78×11.39mm).


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