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13ct Tourmaline (Oval, 19.71×13.14mm, Purple) vs 13ct Quartz (Oval, 20.69×13.79mm, Brown)


Quick summary: When looked from above (face-up position), 13ct Quartz (20.69×13.79mm, oval cut) appears 10% larger than 13ct Tourmaline (19.71×13.14mm, oval cut). See below how they compare side-by-side on a ring and finger.

13ct Tourmaline (oval cut)
vs
 13ct Quartz (oval cut)
purple
 
brown
19.71×13.14 mm 20.69×13.79 mm
actual size
Actual size of 13ct Tourmaline (oval cut, 19.71×13.14mm, Purple color)   Actual size of 13ct Quartz (oval cut, 20.69×13.79mm, Brown color)
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Purple 13ct Tourmaline (oval cut, 19.71×13.14mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Brown 13ct Quartz (oval cut, 20.69×13.79mm) 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
 78% vs 82%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 13ct Tourmaline Oval (19.71×13.14mm, Purple) and 13ct Quartz Oval (20.69×13.79mm, 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.


13 Ct Tourmaline (Oval) 13 Ct Quartz (Oval)
19.71×13.14 mm vs 20.69×13.79 mm
212.37 mm²   233.96 mm²
Face-up size outline for 13ct Quartz (20.69×13.79mm, oval cut)
Face-up size outline for 13ct Tourmaline (19.71×13.14mm, oval cut)
13ct Tourmaline Oval (19.71×13.14mm)
13ct Quartz Oval (20.69×13.79mm)
Difference: 10% (21.59 mm²)
13ct Quartz (Oval, 20.69×13.79mm) has approx. 10% more face-up area than 13ct Tourmaline (Oval, 19.71×13.14mm).


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