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12ct Tourmaline (Round, 14.97×14.97mm, Purple) vs 12ct Quartz (Round, 15.7×15.7mm, Brown)


Quick summary: When looked from above (face-up position), 12ct Quartz (15.7×15.7mm, round cut) appears 10% larger than 12ct Tourmaline (14.97×14.97mm, round cut). See below how they compare side-by-side on a ring and finger.

12ct Tourmaline (round cut)
vs
 12ct Quartz (round cut)
purple
 
brown
14.97×14.97 mm 15.7×15.7 mm
actual size
Actual size of 12ct Tourmaline (round cut, 14.97×14.97mm, Purple color)   Actual size of 12ct Quartz (round cut, 15.7×15.7mm, Brown color)
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Purple 12ct Tourmaline (round cut, 14.97×14.97mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Brown 12ct Quartz (round cut, 15.7×15.7mm) 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
 89% vs 93%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 12ct Tourmaline Round (14.97×14.97mm, Purple) and 12ct Quartz Round (15.7×15.7mm, Brown) 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, Tourmaline will face-up smaller than Quartz for a given carat weight, because it has higher specific gravity (3.06 vs. 2.65 - this means it's "heavier" compared to Quartz 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.


12 Ct Tourmaline (Round) 12 Ct Quartz (Round)
14.97×14.97 mm vs 15.7×15.7 mm
176.01 mm²   193.59 mm²
Face-up size outline for 12ct Quartz (15.7×15.7mm, round cut)
Face-up size outline for 12ct Tourmaline (14.97×14.97mm, round cut)
12ct Tourmaline Round (14.97×14.97mm)
12ct Quartz Round (15.7×15.7mm)
Difference: 10% (17.58 mm²)
12ct Quartz (Round, 15.7×15.7mm) has approx. 10% more face-up area than 12ct Tourmaline (Round, 14.97×14.97mm).


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