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1.25ct Tanzanite (Round, 6.87×6.87mm, Blue) vs 1.42ct Sapphire (Round, 6.72×6.72mm, Blue)


Quick summary: When looked from above (face-up position), 1.25ct Tanzanite (6.87×6.87mm, round cut) appears 5% larger than 1.42ct Sapphire (6.72×6.72mm, round cut). See below how they compare side-by-side on a ring and finger.

1.25ct Tanzanite (round cut)
vs
 1.42ct Sapphire (round cut)
blue
 
blue
6.87×6.87 mm 6.72×6.72 mm
actual size
Actual size of 1.25ct Tanzanite (round cut, 6.87×6.87mm, Blue color)   Actual size of 1.42ct Sapphire (round cut, 6.72×6.72mm, Blue color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Blue 1.25ct Tanzanite (round cut, 6.87×6.87mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Blue 1.42ct Sapphire (round cut, 6.72×6.72mm) 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
 41% vs 40%
Saved...
Ring diameter: 16.9 mm
USA UK Asia EU1 EU2
Actual sizes of 1.25ct Tanzanite Round (6.87×6.87mm, Blue) and 1.42ct Sapphire Round (6.72×6.72mm, 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, Sapphire will face-up smaller than Tanzanite for a given carat weight, because it has higher specific gravity (4 vs. 3.35 - this means it's "heavier" compared to Tanzanite 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.


1.25 Ct Tanzanite (Round) 1.42 Ct Sapphire (Round)
6.87×6.87 mm vs 6.72×6.72 mm
37.07 mm²   35.47 mm²
Face-up size outline for 1.25ct Tanzanite (6.87×6.87mm, round cut)
Face-up size outline for 1.42ct Sapphire (6.72×6.72mm, round cut)
1.25ct Tanzanite Round (6.87×6.87mm)
1.42ct Sapphire Round (6.72×6.72mm)
Difference: 5% (1.6 mm²)
1.25ct Tanzanite (Round, 6.87×6.87mm) has approx. 5% more face-up area than 1.42ct Sapphire (Round, 6.72×6.72mm).


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