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9ct Amethyst (Cabochon, 16.34×10.89mm, Violet) vs 9ct Tanzanite (Cabochon, 15.11×10.07mm, Blue)


Quick summary: When looked from above (face-up position), 9ct Amethyst (16.34×10.89mm, cabochon cut) appears 17% larger than 9ct Tanzanite (15.11×10.07mm, cabochon cut). See below how they compare side-by-side on a ring and finger.

9ct Amethyst (cabochon cut)
vs
 9ct Tanzanite (cabochon cut)
violet
 
blue
16.34×10.89 mm 15.11×10.07 mm
actual size
Actual size of 9ct Amethyst (cabochon cut, 16.34×10.89mm, Violet color)   Actual size of 9ct Tanzanite (cabochon cut, 15.11×10.07mm, Blue color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Violet 9ct Amethyst (cabochon cut, 16.34×10.89mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Blue 9ct Tanzanite (cabochon cut, 15.11×10.07mm) 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
 65% vs 60%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 9ct Amethyst Cabochon (16.34×10.89mm, Violet) and 9ct Tanzanite Cabochon (15.11×10.07mm, 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.


9 Ct Amethyst (Cabochon) 9 Ct Tanzanite (Cabochon)
16.34×10.89 mm vs 15.11×10.07 mm
145.91 mm²   124.77 mm²
Face-up size outline for 9ct Amethyst (16.34×10.89mm, cabochon cut)
Face-up size outline for 9ct Tanzanite (15.11×10.07mm, cabochon cut)
9ct Amethyst Cabochon (16.34×10.89mm)
9ct Tanzanite Cabochon (15.11×10.07mm)
Difference: 17% (21.14 mm²)
9ct Amethyst (Cabochon, 16.34×10.89mm) has approx. 17% more face-up area than 9ct Tanzanite (Cabochon, 15.11×10.07mm).


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