carat vs. color  length*  width*

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* size in mm (optional)

3 Ct Ruby (Emerald)


4 Ct Ruby (Emerald)

9.21×6.82 mm 10.14×7.51 mm
actual size
Actual size of 3ct Ruby   Actual size of 4ct Ruby
Actual size is set for screen Change
Ring: Skin tone:
Ring width: 3.0 mm
Left finger image
Ring on left finger
Red 3ct Ruby on a ring
64 mm
Right finger image
Ring on a right finger
Red 4ct Ruby on a ring
Your settings
Skin tone
Ring diameter
16.9 mm
Ring width
3.0 mm
Finger length
64 mm
Ring diameter: 16.9 mm
Actual sizes of 3ct Ruby Emerald (9.21×6.82mm, Red) and 4ct Ruby Emerald (10.14×7.51mm, Red) 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?

JamesAllen → high-quality gemstones (Rubies, Saphhires, Emeralds) and especially Diamonds, high-end jewelry and competitive prices. Highly recommended.
Amazon → usually offers a good selection from many different vendors. Worth a check.

Face-up Size

The face-up size depends on the shape of the gem, its weight and 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.

3 Ct Ruby (Emerald) 4 Ct Ruby (Emerald)
9.21×6.82 mm vs 10.14×7.51 mm
58.42 mm²   70.82 mm²
Face-up size outline
Face-up size outline
3ct Ruby Emerald (9.21×6.82mm)
4ct Ruby Emerald (10.14×7.51mm)
Difference: 21% (12.4 mm²)
4ct Ruby Emerald (10.14×7.51mm) has approx. 21% more face-up area than 3ct Ruby Emerald (9.21×6.82mm).

Popular comparisons:

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Actual size is currently adjusted to screen.

If your screen (phone, tablet, or monitor) is not in diagonal, then the actual size of a gem, ring and finger will not be shown correctly.