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15 Ct Amethyst (Cushion)

vs

20 Ct Diamond (Cushion)

violet
 
white
15.82×15.82 mm 15.82×15.82 mm
actual size
Actual size of 15ct Amethyst   Actual size of 20ct Diamond
 
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Ring: Skin tone:
Ring width: 3.0 mm
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Left finger image
Ring on left finger
Violet 15ct Amethyst on a ring
64 mm
Right finger image
Ring on a right finger
White 20ct Diamond on a ring
Your settings
Ring
Gold
Skin tone
Light
Ring diameter
16.9 mm
Ring width
3.0 mm
Finger length
64 mm
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Ring diameter: 16.9 mm
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Actual sizes of 15ct Amethyst Cushion (15.82×15.82mm, Violet) and 20ct Diamond Cushion (15.82×15.82mm, White) 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?

JamesAllen → high-quality Diamonds, high-end jewelry and competitive prices. Highly recommended.
Amazon → usually offers a good selection from many different vendors. Worth a check.

Face-up Size

All things being equal, Diamond will face-up smaller than Amethyst for a given carat weight, because it has higher specific gravity (3.52 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.


15 Ct Amethyst (Cushion) 20 Ct Diamond (Cushion)
15.82×15.82 mm vs 15.82×15.82 mm
225.25 mm²   225.25 mm²
Face-up size outline
15ct Amethyst Cushion (15.82×15.82mm)
20ct Diamond Cushion (15.82×15.82mm)
Difference: 0% (0 mm²)
15ct Amethyst Cushion (15.82×15.82mm) and 20ct Diamond Cushion (15.82×15.82mm) have the same face-up area.


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If your screen (phone, tablet, or monitor) is not in diagonal, then the actual size of a gem, ring and finger will not be shown correctly.