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0.25ct Spinel (Round, 3.9×3.9mm, Red) vs 0.1ct Tourmaline (Round, 3.02×3.02mm, Violet)


Quick summary: When looked from above (face-up position), 0.25ct Spinel (3.9×3.9mm, round cut) appears 67% larger than 0.1ct Tourmaline (3.02×3.02mm, round cut). See below how they compare side-by-side on a ring and finger.

0.25ct Spinel (round cut)
vs
 0.1ct Tourmaline (round cut)
red
 
violet
3.9×3.9 mm 3.02×3.02 mm
actual size
Actual size of 0.25ct Spinel (round cut, 3.9×3.9mm, Red color)   Actual size of 0.1ct Tourmaline (round cut, 3.02×3.02mm, Violet color)
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Red 0.25ct Spinel (round cut, 3.9×3.9mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Violet 0.1ct Tourmaline (round cut, 3.02×3.02mm) 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
 24% vs 18%
Saved...
Ring diameter: 16.9 mm
USA UK Asia EU1 EU2
Actual sizes of 0.25ct Spinel Round (3.9×3.9mm, Red) and 0.1ct Tourmaline Round (3.02×3.02mm, Violet) 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, Spinel will face-up smaller than Tourmaline for a given carat weight, because it has higher specific gravity (3.6 vs. 3.06 - this means it's "heavier" compared to Tourmaline 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.


0.25 Ct Spinel (Round) 0.1 Ct Tourmaline (Round)
3.9×3.9 mm vs 3.02×3.02 mm
11.95 mm²   7.16 mm²
Face-up size outline for 0.25ct Spinel (3.9×3.9mm, round cut)
Face-up size outline for 0.1ct Tourmaline (3.02×3.02mm, round cut)
0.25ct Spinel Round (3.9×3.9mm)
0.1ct Tourmaline Round (3.02×3.02mm)
Difference: 67% (4.79 mm²)
0.25ct Spinel (Round, 3.9×3.9mm) has approx. 67% more face-up area than 0.1ct Tourmaline (Round, 3.02×3.02mm).


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