carat vs. color  length*  width*

(or examine a single gem)
* size in mm (optional)

10.5 Ct Amethyst (Cushion)


10.5 Ct Diamond (Princess)

14.05×14.05 mm 12.07×12.07 mm
actual size
Actual size of 10.5ct Amethyst   Actual size of 10.5ct Diamond
Actual size is set for screen Change
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Violet 10.5ct Amethyst on a ring
64 mm
Right finger image
Ring on a right finger
White 10.5ct Diamond on a ring
Your settings
Skin tone
Ring diameter
16.9 mm
Ring width
3.0 mm
Finger length
64 mm
Ring diameter: 16.9 mm
Actual sizes of 10.5ct Amethyst Cushion (14.05×14.05mm, Violet) and 10.5ct Diamond Princess (12.07×12.07mm, 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.

10.5 Ct Amethyst (Cushion) 10.5 Ct Diamond (Princess)
14.05×14.05 mm vs 12.07×12.07 mm
177.66 mm²   145.68 mm²
Face-up size outline
Face-up size outline
10.5ct Amethyst Cushion (14.05×14.05mm)
10.5ct Diamond Princess (12.07×12.07mm)
Difference: 22% (31.98 mm²)
10.5ct Amethyst Cushion (14.05×14.05mm) has approx. 22% more face-up area than 10.5ct Diamond Princess (12.07×12.07mm).

Popular comparisons:

Enter your screen size (diagonal)

My screen size is  inches

Actual size is currently adjusted to screen.

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.