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18ct Tanzanite (Trillion, 20.32×20.32mm, Blue) vs 18ct Aquamarine (Trillion, 21.79×21.79mm, Light Blue)


Quick summary: When looked from above (face-up position), 18ct Aquamarine (21.79×21.79mm, trillion cut) appears 15% larger than 18ct Tanzanite (20.32×20.32mm, trillion cut). See below how they compare side-by-side on a ring and finger.

18ct Tanzanite (trillion cut)
vs
 18ct Aquamarine (trillion cut)
blue
 
light blue
20.32×20.32 mm 21.79×21.79 mm
actual size
Actual size of 18ct Tanzanite (trillion cut, 20.32×20.32mm, Blue color)   Actual size of 18ct Aquamarine (trillion cut, 21.79×21.79mm, Light Blue color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Blue 18ct Tanzanite (trillion cut, 20.32×20.32mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Light Blue 18ct Aquamarine (trillion cut, 21.79×21.79mm) 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
 121% vs 129%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 18ct Tanzanite Trillion (20.32×20.32mm, Blue) and 18ct Aquamarine Trillion (21.79×21.79mm, Light 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 Aquamarine for a given carat weight, because it has higher specific gravity (3.35 vs. 2.72 - this means it's "heavier" compared to Aquamarine 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.


18 Ct Tanzanite (Trillion) 18 Ct Aquamarine (Trillion)
20.32×20.32 mm vs 21.79×21.79 mm
256 mm²   294.38 mm²
Face-up size outline for 18ct Aquamarine (21.79×21.79mm, trillion cut)
Face-up size outline for 18ct Tanzanite (20.32×20.32mm, trillion cut)
18ct Tanzanite Trillion (20.32×20.32mm)
18ct Aquamarine Trillion (21.79×21.79mm)
Difference: 15% (38.38 mm²)
18ct Aquamarine (Trillion, 21.79×21.79mm) has approx. 15% more face-up area than 18ct Tanzanite (Trillion, 20.32×20.32mm).


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