Fascinating Diamonds

Diamond Size Chart

Radiant Diamond Size Chart

Radiant cut diamonds have trimmed corners and a brilliant cut style that blends round sparkle with an emerald-like outline.

Average Radiant Diamond Sizes

  • 0.50 carat ≈ 5 x 4 mm
  • 1.00 carat ≈ 6.5 x 5.5 mm
  • 2.00 carat ≈ 8 x 7 mm

Tip: Rectangular radiants often look bigger than square ones of the same carat.

Select a diamond shape.

  • Round
  • Princess
  • Asscher
  • Heart
  • Marquise
  • Oval
  • Radiant
  • Emerald
  • Pear
  • Cushion

MM Size Carat Weight
4.3x3 mm.0.25 ct.
4.5x3.5 mm.0.34 ct.
6x3 mm.0.41 ct.
6x4 mm.0.50 ct.
6.5x4.5 mm.0.75 ct.
7x5 mm.1.00 ct.
7.3x5.5 mm.1.25 ct.
7.5x5.8 mm.1.50 ct.
8x6 mm.1.75 ct.
Radiant Diamond Illustration
MM Size Carat Weight
8.2x6.2 mm.2.00 ct.
8.5x6.5 mm.2.25 ct.
9x7 mm.2.50 ct.
9.5x7.5 mm.3.00 ct.
10x7 mm.3.31 ct.
10x8 mm.3.50 ct.
10.2x8.2 mm.4.00 ct.
10.5x8.5 mm.4.50 ct.
11x9 mm.5.00 ct.
MM Size Carat Weight
11.5x10 mm.6.45 ct.
12x9 mm.6.06 ct.
13x9 mm.6.54 ct.
13.2x9.2 mm.6.79 ct.
14x10 mm.8.47 ct.
13x11 mm.9.33 ct.
13.5x11.5 mm.10.19 ct.
15x11 mm.11.48 ct.
14x12 mm.12.14 ct.
16x12 mm.14.22 ct.
4cs of diamond guide

4cs of diamond guide

Begin your journey with our comprehensive online diamond education, and when you`re ready, our team of experts is here to answer your more detailed questions.

Loose Diamonds

Loose Diamonds

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Frequently Asked Questions

How do I use the Marquise Cut Diamond size chart?

The chart shows how each carat weight translates into millimeter dimensions, helping you understand the actual size of your marquise diamond before buying.

Do marquise diamonds look bigger than other shapes?

Yes, marquise diamonds appear larger than most shapes of the same carat because of their elongated form and pointed ends, which create the illusion of greater size.

What is the ideal length-to-width ratio for a marquise cut diamond?

A ratio between 1.75 and 2.25 is preferred for a classic marquise shape that looks elegant and balanced.

Why does my marquise diamond show a dark line in the center?

That’s known as the “bow-tie effect.” It happens due to light reflection patterns and can be minimized by choosing a well-cut diamond.

What size marquise diamond is best for an engagement ring?

Marquise diamonds between 0.75 and 2.0 carats are popular for engagement rings, offering both brilliance and finger-flattering length.

Are marquise diamonds more fragile than other cuts?

Their pointed ends can be more delicate, so choosing a protective setting like a bezel or V-prong helps prevent chipping.

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