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18ct Fluorite (Cabochon, 19.37×12.91mm, Bluish Green) vs 18ct Topaz (Cabochon, 18.71×12.47mm, Blue)


Quick summary: When looked from above (face-up position), 18ct Fluorite (19.37×12.91mm, cabochon cut) appears 7% larger than 18ct Topaz (18.71×12.47mm, cabochon cut). See below how they compare side-by-side on a ring and finger.

18ct Fluorite (cabochon cut)
vs
 18ct Topaz (cabochon cut)
bluish green
 
blue
19.37×12.91 mm 18.71×12.47 mm
actual size
Actual size of 18ct Fluorite (cabochon cut, 19.37×12.91mm, Bluish Green color)   Actual size of 18ct Topaz (cabochon cut, 18.71×12.47mm, Blue color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Bluish Green 18ct Fluorite (cabochon cut, 19.37×12.91mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Blue 18ct Topaz (cabochon cut, 18.71×12.47mm) 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 74%
Saved...
Ring diameter: 16.9 mm
USA UK Asia EU1 EU2
Actual sizes of 18ct Fluorite Cabochon (19.37×12.91mm, Bluish Green) and 18ct Topaz Cabochon (18.71×12.47mm, Blue) 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 Fluorite for a given carat weight, because it has higher specific gravity (3.53 vs. 3.18 - this means it's "heavier" compared to Fluorite 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.


18 Ct Fluorite (Cabochon) 18 Ct Topaz (Cabochon)
19.37×12.91 mm vs 18.71×12.47 mm
205.05 mm²   191.32 mm²
Face-up size outline for 18ct Fluorite (19.37×12.91mm, cabochon cut)
Face-up size outline for 18ct Topaz (18.71×12.47mm, cabochon cut)
18ct Fluorite Cabochon (19.37×12.91mm)
18ct Topaz Cabochon (18.71×12.47mm)
Difference: 7% (13.73 mm²)
18ct Fluorite (Cabochon, 19.37×12.91mm) has approx. 7% more face-up area than 18ct Topaz (Cabochon, 18.71×12.47mm).


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