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4.5ct Amethyst (Trillion, 13.84×13.84mm, Violet) vs 4.5ct Tanzanite (Trillion, 12.8×12.8mm, Blue)


Quick summary: When looked from above (face-up position), 4.5ct Amethyst (13.84×13.84mm, trillion cut) appears 17% larger than 4.5ct Tanzanite (12.8×12.8mm, trillion cut). See below how they compare side-by-side on a ring and finger.

4.5ct Amethyst (trillion cut)
vs
4.5ct Tanzanite (trillion cut)
violet
 
blue
13.84×13.84 mm 12.8×12.8 mm
actual size
Actual size of 4.5ct Amethyst (trillion cut, 13.84×13.84mm, Violet color)   Actual size of 4.5ct Tanzanite (trillion cut, 12.8×12.8mm, Blue color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Violet 4.5ct Amethyst (trillion cut, 13.84×13.84mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Blue 4.5ct Tanzanite (trillion cut, 12.8×12.8mm) 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
82% vs 76%
Saved...
Ring diameter: 16.9 mm
USA UK Asia EU1 EU2
Actual sizes of 4.5ct Amethyst Trillion (13.84×13.84mm, Violet) and 4.5ct Tanzanite Trillion (12.8×12.8mm, 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, Tanzanite will face-up smaller than Amethyst for a given carat weight, because it has higher specific gravity (3.35 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.


4.5 Ct Amethyst (Trillion) 4.5 Ct Tanzanite (Trillion)
13.84×13.84 mm vs 12.8×12.8 mm
118.76 mm²   101.58 mm²
Face-up size outline for 4.5ct Amethyst (13.84×13.84mm, trillion cut)
Face-up size outline for 4.5ct Tanzanite (12.8×12.8mm, trillion cut)
4.5ct Amethyst Trillion (13.84×13.84mm)
4.5ct Tanzanite Trillion (12.8×12.8mm)
Difference: 17% (17.18 mm²)
4.5ct Amethyst (Trillion, 13.84×13.84mm) has approx. 17% more face-up area than 4.5ct Tanzanite (Trillion, 12.8×12.8mm).


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