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20ct Topaz (Cabochon, 19.37×12.91mm, Blue) vs 20ct Quartz (Cabochon, 21.32×14.21mm, Brown)


Quick summary: When looked from above (face-up position), 20ct Quartz (21.32×14.21mm, cabochon cut) appears 21% larger than 20ct Topaz (19.37×12.91mm, cabochon cut). See below how they compare side-by-side on a ring and finger.

20ct Topaz (cabochon cut)
vs
20ct Quartz (cabochon cut)
blue
 
brown
19.37×12.91 mm 21.32×14.21 mm
actual size
Actual size of 20ct Topaz (cabochon cut, 19.37×12.91mm, Blue color)   Actual size of 20ct Quartz (cabochon cut, 21.32×14.21mm, Brown color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Blue 20ct Topaz (cabochon cut, 19.37×12.91mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Brown 20ct Quartz (cabochon cut, 21.32×14.21mm) 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
77% vs 85%
Saved...
Ring diameter: 16.9 mm
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Actual sizes of 20ct Topaz Cabochon (19.37×12.91mm, Blue) and 20ct Quartz Cabochon (21.32×14.21mm, 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, Topaz will face-up smaller than Quartz for a given carat weight, because it has higher specific gravity (3.53 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.


20 Ct Topaz (Cabochon) 20 Ct Quartz (Cabochon)
19.37×12.91 mm vs 21.32×14.21 mm
205.05 mm²   248.42 mm²
Face-up size outline for 20ct Quartz (21.32×14.21mm, cabochon cut)
Face-up size outline for 20ct Topaz (19.37×12.91mm, cabochon cut)
20ct Topaz Cabochon (19.37×12.91mm)
20ct Quartz Cabochon (21.32×14.21mm)
Difference: 21% (43.37 mm²)
20ct Quartz (Cabochon, 21.32×14.21mm) has approx. 21% more face-up area than 20ct Topaz (Cabochon, 19.37×12.91mm).


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