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40ct Diamond (Round, 22.23×22.23mm, White) vs 40ct Topaz (Round, 21.32×21.32mm, Blue)


Quick summary: When looked from above (face-up position), 40ct Diamond (22.23×22.23mm, round cut) appears 9% larger than 40ct Topaz (21.32×21.32mm, round cut). See below how they compare side-by-side on a ring and finger.

40ct Diamond (round cut)
vs
 40ct Topaz (round cut)
white
 
blue
22.23×22.23 mm 21.32×21.32 mm
actual size
Actual size of 40ct Diamond (round cut, 22.23×22.23mm, White color)   Actual size of 40ct Topaz (round cut, 21.32×21.32mm, Blue color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
White 40ct Diamond (round cut, 22.23×22.23mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Blue 40ct Topaz (round cut, 21.32×21.32mm) 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
 132% vs 127%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 40ct Diamond Round (22.23×22.23mm, White) and 40ct Topaz Round (21.32×21.32mm, 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, Topaz will face-up slightly smaller than Diamond for a given carat weight, because it has higher specific gravity (3.53 vs. 3.52 - this means it's "slightly heavier" compared to Diamond 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.


40 Ct Diamond (Round) 40 Ct Topaz (Round)
22.23×22.23 mm vs 21.32×21.32 mm
388.12 mm²   357 mm²
Face-up size outline for 40ct Diamond (22.23×22.23mm, round cut)
Face-up size outline for 40ct Topaz (21.32×21.32mm, round cut)
40ct Diamond Round (22.23×22.23mm)
40ct Topaz Round (21.32×21.32mm)
Difference: 9% (31.12 mm²)
40ct Diamond (Round, 22.23×22.23mm) has approx. 9% more face-up area than 40ct Topaz (Round, 21.32×21.32mm).


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