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Carat

Understanding carat weight and its impact on diamond size and value.

What is Carat?

Carat refers to the weight of a diamond. Diamonds are all weighed in metric carats rather than grams or ounces. This is a standard industry practice around the world.

Diamond is expressed to the hundredth of a carat. Carat weight of less than a carat is expressed in points. So, for example, a 0.75ct diamond will be 75 points. Most jewellers will refer to carat weight in this terminology.

Another way to explain this would be using pounds, 100 pence equals 1 whole pound. Therefore 50pts will be 0.50ct and so on.

How to Work Out Carat Weight?

A common misconception is that it refers to the physical size of a diamond, which is incorrect. The diamond weight does not govern the size of stone.

We always recommend trying a range of carat weight on to determine which will be best for you. This way you will also be able to assess the visible size. For those who can't come into our store to view diamonds we have the chart below to give you an indication on size.

Carat Weight0.25ct0.50ct0.75ct1ct1.50ct2ct3ct4ct5ctCarat Weight
Round
Round
4mm5mm5.50mm6.50mm7.50mm8mm9.40mm10.40mm11.20mm
Round
Princess
Princess
3.50mm4.50mm5mm5.50mm6.80mm7.50mm8mm8.90mm9.70mm
Princess
Heart
Heart
4x4mm5x5mm6x6mm6.50x6.50mm7x7mm8x8mm9x9mm10x10mm11x11mm
Heart
Emerald
Emerald
4x3mm6x4mm6.50x4.50mm7x5mm8x6mm8.50x6.50mm10x8mm11x9mm10x10mm
Emerald
Asscher
Asscher
3.70mm4.40mm5mm5.80mm6.40mm7mm8.10mm9mm9.60mm
Asscher
Marquise
Marquise
5x3mm8x4mm9x4.50mm10x4.75mm11x5mm12x6mm14x7mm15x7mm16x8mm
Marquise
Radiant
Radiant
3.50x3mm5x4.50mm5.50x5mm6x5.50mm7x6mm7.50x7mm8.50x7.50mm9.50x8.50mm10x9mm
Radiant
Cushion
Cushion
4x3.50mm5x4.50mm6x5mm6.50x5.50mm7.50x6.50mm8x7mm9x8mm10x8.50mm10x9.50mm
Cushion
Oval
Oval
5x3mm6x4mm7x5mm7.50x5.50mm8.50x6.50mm9x7mm10x8mm11x9mm12x10mm
Oval
Pear
Pear
4x2mm6x4mm7x5mm8x5mm9x6mm10x7mm12x8mm14x9mm15x10mm
Pear