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0.42ct Amethyst (Round, 5.14×5.14mm, Violet) vs 2.7ct Tanzanite (Round, 8.88×8.88mm, Blue)


Quick summary: When looked from above (face-up position), 2.7ct Tanzanite (8.88×8.88mm, round cut) appears 3 times larger than 0.42ct Amethyst (5.14×5.14mm, round cut). See below how they compare side-by-side on a ring and finger.

0.42ct Amethyst (round cut)
vs
 2.7ct Tanzanite (round cut)
violet
 
blue
5.14×5.14 mm 8.88×8.88 mm
actual size
Actual size of 0.42ct Amethyst (round cut, 5.14×5.14mm, Violet color)   Actual size of 2.7ct Tanzanite (round cut, 8.88×8.88mm, Blue color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Violet 0.42ct Amethyst (round cut, 5.14×5.14mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Blue 2.7ct Tanzanite (round cut, 8.88×8.88mm) 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
 31% vs 53%
Saved...
Ring diameter: 16.9 mm
USA UK Asia EU1 EU2
Actual sizes of 0.42ct Amethyst Round (5.14×5.14mm, Violet) and 2.7ct Tanzanite Round (8.88×8.88mm, 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.


0.42 Ct Amethyst (Round) 2.7 Ct Tanzanite (Round)
5.14×5.14 mm vs 8.88×8.88 mm
20.75 mm²   61.93 mm²
Face-up size outline for 2.7ct Tanzanite (8.88×8.88mm, round cut)
Face-up size outline for 0.42ct Amethyst (5.14×5.14mm, round cut)
0.42ct Amethyst Round (5.14×5.14mm)
2.7ct Tanzanite Round (8.88×8.88mm)
Difference: 198% (41.18 mm²)
2.7ct Tanzanite (Round, 8.88×8.88mm) has approx. 198% more face-up area than 0.42ct Amethyst (Round, 5.14×5.14mm). In other words, it's 2.98x larger.


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