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2.5ct Topaz (Oval, 10.7×7.13mm, Blue) vs 4ct Diamond (Emerald, 10.61×7.86mm, White)


Quick summary: When looked from above (face-up position), 4ct Diamond (10.61×7.86mm, emerald cut) appears 24% larger than 2.5ct Topaz (10.7×7.13mm, oval cut). See below how they compare side-by-side on a ring and finger.

2.5ct Topaz (oval cut)
vs
 4ct Diamond (emerald cut)
blue
 
white
10.7×7.13 mm 10.61×7.86 mm
actual size
Actual size of 2.5ct Topaz (oval cut, 10.7×7.13mm, Blue color)   Actual size of 4ct Diamond (emerald cut, 10.61×7.86mm, White color)
 
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Ring: Skin tone:
Ring width: 3.0 mm
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Left finger image
Ring on left finger
Blue 2.5ct Topaz (oval cut, 10.7×7.13mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
White 4ct Diamond (emerald cut, 10.61×7.86mm) 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
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Ring diameter: 16.9 mm
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Actual sizes of 2.5ct Topaz Oval (10.7×7.13mm, Blue) and 4ct Diamond Emerald (10.61×7.86mm, 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?

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.


2.5 Ct Topaz (Oval) 4 Ct Diamond (Emerald)
10.7×7.13 mm vs 10.61×7.86 mm
62.56 mm²   77.56 mm²
Face-up size outline for 4ct Diamond (10.61×7.86mm, emerald cut)
Face-up size outline for 2.5ct Topaz (10.7×7.13mm, oval cut)
2.5ct Topaz Oval (10.7×7.13mm)
4ct Diamond Emerald (10.61×7.86mm)
Difference: 24% (15 mm²)
4ct Diamond Emerald (10.61×7.86mm) has approx. 24% more face-up area than 2.5ct Topaz Oval (10.7×7.13mm).


Popular comparisons:

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