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30ct Tourmaline (Marquise, 33.04×16.52mm, Purple) vs 30ct Quartz (Marquise, 34.66×17.33mm, Brown)


Quick summary: When looked from above (face-up position), 30ct Quartz (34.66×17.33mm, marquise cut) appears 10% larger than 30ct Tourmaline (33.04×16.52mm, marquise cut). See below how they compare side-by-side on a ring and finger.

30ct Tourmaline (marquise cut)
vs
 30ct Quartz (marquise cut)
purple
 
brown
33.04×16.52 mm 34.66×17.33 mm
actual size
Actual size of 30ct Tourmaline (marquise cut, 33.04×16.52mm, Purple color)   Actual size of 30ct Quartz (marquise cut, 34.66×17.33mm, Brown color)
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Purple 30ct Tourmaline (marquise cut, 33.04×16.52mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Brown 30ct Quartz (marquise cut, 34.66×17.33mm) 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
 98% vs 103%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 30ct Tourmaline Marquise (33.04×16.52mm, Purple) and 30ct Quartz Marquise (34.66×17.33mm, 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.


30 Ct Tourmaline (Marquise) 30 Ct Quartz (Marquise)
33.04×16.52 mm vs 34.66×17.33 mm
387.53 mm²   426.47 mm²
Face-up size outline for 30ct Quartz (34.66×17.33mm, marquise cut)
Face-up size outline for 30ct Tourmaline (33.04×16.52mm, marquise cut)
30ct Tourmaline Marquise (33.04×16.52mm)
30ct Quartz Marquise (34.66×17.33mm)
Difference: 10% (38.94 mm²)
30ct Quartz (Marquise, 34.66×17.33mm) has approx. 10% more face-up area than 30ct Tourmaline (Marquise, 33.04×16.52mm).


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