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3.7ct Topaz (Oval, 12.2×8.13mm, Blue) vs 7.8ct Topaz (Oval, 15.65×10.43mm, Blue)


Quick summary: When looked from above (face-up position), 7.8ct Topaz (15.65×10.43mm, oval cut) appears 65% larger than 3.7ct Topaz (12.2×8.13mm, oval cut). See below how they compare side-by-side on a ring and finger.

3.7ct Topaz (oval cut)
vs
 7.8ct Topaz (oval cut)
blue
 
blue
12.2×8.13 mm 15.65×10.43 mm
actual size
Actual size of 3.7ct Topaz (oval cut, 12.2×8.13mm, Blue color)   Actual size of 7.8ct Topaz (oval cut, 15.65×10.43mm, Blue color)
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Blue 3.7ct Topaz (oval cut, 12.2×8.13mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Blue 7.8ct Topaz (oval cut, 15.65×10.43mm) 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
 49% vs 62%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 3.7ct Topaz Oval (12.2×8.13mm, Blue) and 7.8ct Topaz Oval (15.65×10.43mm, 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

The face-up size depends on the shape of the gem, its weight and 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.


3.7 Ct Topaz (Oval) 7.8 Ct Topaz (Oval)
12.2×8.13 mm vs 15.65×10.43 mm
81.33 mm²   133.85 mm²
Face-up size outline for 7.8ct Topaz (15.65×10.43mm, oval cut)
Face-up size outline for 3.7ct Topaz (12.2×8.13mm, oval cut)
3.7ct Topaz Oval (12.2×8.13mm)
7.8ct Topaz Oval (15.65×10.43mm)
Difference: 65% (52.52 mm²)
7.8ct Topaz (Oval, 15.65×10.43mm) has approx. 65% more face-up area than 3.7ct Topaz (Oval, 12.2×8.13mm).


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