×
carat vs. color  length*  width*
  ×

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

1ct Alexandrite (Cushion, 5.5×5.5mm, Bluish Green) vs 1ct Topaz (Round, 6×6mm, Dark Bluish Green)


Quick summary: When looked from above (face-up position), 1ct Topaz (6×6mm, round cut) appears 4% larger than 1ct Alexandrite (5.5×5.5mm, cushion cut). See below how they compare side-by-side on a ring and finger.

1ct Alexandrite (cushion cut)
vs
1ct Topaz (round cut)
bluish green
 
dark bluish green
5.5×5.5 mm 6×6 mm
actual size
Actual size of 1ct Alexandrite (cushion cut, 5.5×5.5mm, Bluish Green color)   Actual size of 1ct Topaz (round cut, 6×6mm, Dark Bluish Green color)
 
Actual size is set for screen
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Bluish Green 1ct Alexandrite (cushion cut, 5.5×5.5mm) on a left ring and finger
64 mm
Right finger image
Ring on a right finger
Dark Bluish Green 1ct Topaz (round cut, 6×6mm) 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
33% vs 36%
Saved...
Ring diameter: 16.9 mm
USA UK Asia EU1 EU2
Actual sizes of 1ct Alexandrite Cushion (5.5×5.5mm, Bluish Green) and 1ct Topaz Round (6×6mm, Dark Bluish Green) 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.


1 Ct Alexandrite (Cushion) 1 Ct Topaz (Round)
5.5×5.5 mm vs 6×6 mm
27.23 mm²   28.27 mm²
Face-up size outline for 1ct Topaz (6×6mm, round cut)
Face-up size outline for 1ct Alexandrite (5.5×5.5mm, cushion cut)
1ct Alexandrite Cushion (5.5×5.5mm)
1ct Topaz Round (6×6mm)
Difference: 4% (1.04 mm²)
1ct Topaz (Round, 6×6mm) has approx. 4% more face-up area than 1ct Alexandrite (Cushion, 5.5×5.5mm).


Popular comparisons: