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4.5ct Amethyst (Asscher, 10.1×10.1mm, Violet) vs 4.5ct Tanzanite (Asscher, 9.34×9.34mm, Blue)


Quick summary: When looked from above (face-up position), 4.5ct Amethyst (10.1×10.1mm, asscher cut) appears 17% larger than 4.5ct Tanzanite (9.34×9.34mm, asscher cut). See below how they compare side-by-side on a ring and finger.

4.5ct Amethyst (asscher cut)
vs
 4.5ct Tanzanite (asscher cut)
violet
 
blue
10.1×10.1 mm 9.34×9.34 mm
actual size
Actual size of 4.5ct Amethyst (asscher cut, 10.1×10.1mm, Violet color)   Actual size of 4.5ct Tanzanite (asscher cut, 9.34×9.34mm, 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 (asscher cut, 10.1×10.1mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Blue 4.5ct Tanzanite (asscher cut, 9.34×9.34mm) 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
 60% vs 56%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 4.5ct Amethyst Asscher (10.1×10.1mm, Violet) and 4.5ct Tanzanite Asscher (9.34×9.34mm, 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 (Asscher) 4.5 Ct Tanzanite (Asscher)
10.1×10.1 mm vs 9.34×9.34 mm
93.85 mm²   80.26 mm²
Face-up size outline for 4.5ct Amethyst (10.1×10.1mm, asscher cut)
Face-up size outline for 4.5ct Tanzanite (9.34×9.34mm, asscher cut)
4.5ct Amethyst Asscher (10.1×10.1mm)
4.5ct Tanzanite Asscher (9.34×9.34mm)
Difference: 17% (13.59 mm²)
4.5ct Amethyst (Asscher, 10.1×10.1mm) has approx. 17% more face-up area than 4.5ct Tanzanite (Asscher, 9.34×9.34mm).


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