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17ct Tourmaline (Trillion, 20.55×20.55mm, Purple) vs 17ct Quartz (Trillion, 21.56×21.56mm, Brown)


Quick summary: When looked from above (face-up position), 17ct Quartz (21.56×21.56mm, trillion cut) appears 10% larger than 17ct Tourmaline (20.55×20.55mm, trillion cut). See below how they compare side-by-side on a ring and finger.

17ct Tourmaline (trillion cut)
vs
 17ct Quartz (trillion cut)
purple
 
brown
20.55×20.55 mm 21.56×21.56 mm
actual size
Actual size of 17ct Tourmaline (trillion cut, 20.55×20.55mm, Purple color)   Actual size of 17ct Quartz (trillion cut, 21.56×21.56mm, Brown color)
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Purple 17ct Tourmaline (trillion cut, 20.55×20.55mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Brown 17ct Quartz (trillion cut, 21.56×21.56mm) 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
 122% vs 128%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 17ct Tourmaline Trillion (20.55×20.55mm, Purple) and 17ct Quartz Trillion (21.56×21.56mm, 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.


17 Ct Tourmaline (Trillion) 17 Ct Quartz (Trillion)
20.55×20.55 mm vs 21.56×21.56 mm
261.83 mm²   288.2 mm²
Face-up size outline for 17ct Quartz (21.56×21.56mm, trillion cut)
Face-up size outline for 17ct Tourmaline (20.55×20.55mm, trillion cut)
17ct Tourmaline Trillion (20.55×20.55mm)
17ct Quartz Trillion (21.56×21.56mm)
Difference: 10% (26.37 mm²)
17ct Quartz (Trillion, 21.56×21.56mm) has approx. 10% more face-up area than 17ct Tourmaline (Trillion, 20.55×20.55mm).


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