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17ct Tourmaline (Cabochon, 19.25×12.83mm, Purple) vs 17ct Quartz (Cabochon, 20.19×13.46mm, Brown)


Quick summary: When looked from above (face-up position), 17ct Quartz (20.19×13.46mm, cabochon cut) appears 10% larger than 17ct Tourmaline (19.25×12.83mm, cabochon cut). See below how they compare side-by-side on a ring and finger.

17ct Tourmaline (cabochon cut)
vs
 17ct Quartz (cabochon cut)
purple
 
brown
19.25×12.83 mm 20.19×13.46 mm
actual size
Actual size of 17ct Tourmaline (cabochon cut, 19.25×12.83mm, Purple color)   Actual size of 17ct Quartz (cabochon cut, 20.19×13.46mm, 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 (cabochon cut, 19.25×12.83mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Brown 17ct Quartz (cabochon cut, 20.19×13.46mm) 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
 76% vs 80%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 17ct Tourmaline Cabochon (19.25×12.83mm, Purple) and 17ct Quartz Cabochon (20.19×13.46mm, 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 (Cabochon) 17 Ct Quartz (Cabochon)
19.25×12.83 mm vs 20.19×13.46 mm
202.52 mm²   222.84 mm²
Face-up size outline for 17ct Quartz (20.19×13.46mm, cabochon cut)
Face-up size outline for 17ct Tourmaline (19.25×12.83mm, cabochon cut)
17ct Tourmaline Cabochon (19.25×12.83mm)
17ct Quartz Cabochon (20.19×13.46mm)
Difference: 10% (20.32 mm²)
17ct Quartz (Cabochon, 20.19×13.46mm) has approx. 10% more face-up area than 17ct Tourmaline (Cabochon, 19.25×12.83mm).


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