×
carat vs. color  length*  width*
  ×

(or examine a )
* size in mm (optional)

17ct Alexandrite (Heart, 16.47×16.47mm, Bluish Green) vs 17ct Topaz (Heart, 16.78×16.78mm, Blue)


Quick summary: When looked from above (face-up position), 17ct Topaz (16.78×16.78mm, heart cut) appears 4% larger than 17ct Alexandrite (16.47×16.47mm, heart cut). See below how they compare side-by-side on a ring and finger.

17ct Alexandrite (heart cut)
vs
17ct Topaz (heart cut)
bluish green
 
blue
16.47×16.47 mm 16.78×16.78 mm
actual size
Actual size of 17ct Alexandrite (heart cut, 16.47×16.47mm, Bluish Green color)   Actual size of 17ct Topaz (heart cut, 16.78×16.78mm, 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 17ct Alexandrite (heart cut, 16.47×16.47mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Blue 17ct Topaz (heart cut, 16.78×16.78mm) 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 100%
Saved...
Ring diameter: 16.9 mm
USA UK Asia EU1 EU2
Actual sizes of 17ct Alexandrite Heart (16.47×16.47mm, Bluish Green) and 17ct Topaz Heart (16.78×16.78mm, 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, Alexandrite will face-up smaller than Topaz for a given carat weight, because it has higher specific gravity (3.73 vs. 3.53 - this means it's "heavier" compared to Topaz 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 Alexandrite (Heart) 17 Ct Topaz (Heart)
16.47×16.47 mm vs 16.78×16.78 mm
195.31 mm²   202.73 mm²
Face-up size outline for 17ct Topaz (16.78×16.78mm, heart cut)
Face-up size outline for 17ct Alexandrite (16.47×16.47mm, heart cut)
17ct Alexandrite Heart (16.47×16.47mm)
17ct Topaz Heart (16.78×16.78mm)
Difference: 4% (7.42 mm²)
17ct Topaz (Heart, 16.78×16.78mm) has approx. 4% more face-up area than 17ct Alexandrite (Heart, 16.47×16.47mm).


Popular comparisons: