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8ct Amethyst (Cabochon, 16×12mm, Dark Violet) vs 4ct Quartz (Cabochon, 12.47×8.31mm, Light Bluish Green)


Quick summary: When looked from above (face-up position), 8ct Amethyst (16×12mm, cabochon cut) appears 85% larger than 4ct Quartz (12.47×8.31mm, cabochon cut). See below how they compare side-by-side on a ring and finger.

8ct Amethyst (cabochon cut)
vs
 4ct Quartz (cabochon cut)
dark violet
 
light bluish green
16×12 mm 12.47×8.31 mm
actual size
Actual size of 8ct Amethyst (cabochon cut, 16×12mm, Dark Violet color)   Actual size of 4ct Quartz (cabochon cut, 12.47×8.31mm, Light Bluish Green color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Dark Violet 8ct Amethyst (cabochon cut, 16×12mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Light Bluish Green 4ct Quartz (cabochon cut, 12.47×8.31mm) 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
 72% vs 50%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 8ct Amethyst Cabochon (16×12mm, Dark Violet) and 4ct Quartz Cabochon (12.47×8.31mm, Light Bluish Green) 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

Amethyst and Quartz have the same specific gravity so their face-up size depends on the weight, shape and 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.


8 Ct Amethyst (Cabochon) 4 Ct Quartz (Cabochon)
16×12 mm vs 12.47×8.31 mm
157.44 mm²   84.97 mm²
Face-up size outline for 8ct Amethyst (16×12mm, cabochon cut)
Face-up size outline for 4ct Quartz (12.47×8.31mm, cabochon cut)
8ct Amethyst Cabochon (16×12mm)
4ct Quartz Cabochon (12.47×8.31mm)
Difference: 85% (72.47 mm²)
8ct Amethyst (Cabochon, 16×12mm) has approx. 85% more face-up area than 4ct Quartz (Cabochon, 12.47×8.31mm).


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