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Diamond Carat Weight

What is diamond carat weight and why is it so important? Read our guide to learn the basics.

What is Diamond Carat Weight?

Whilst reflective of size, a carat measurement is actually indicative of the weight of the stone. Therefore, while a stone may have a high carat weight, it may have been cut poorly meaning the stone doesn’t appear as large when viewed from the top. This is one of the reasons we recommend you prioritise cut over carat.

One carat weighs 200 milligrams, or one fifth of a gram. In reality, few diamonds actually weigh exactly one or two carats. In order to provide a more accurate weight for all diamonds, carats are divided into hundredths. As such, a half-carat diamond will also be referred to as a 0.50ct or 50 point stone.

Large diamonds are a lot rarer than smaller stones, which is reflected by their exponentially increasing value. At Hearts of London, we source centre diamonds from 0.30 carats upwards. As we work to optimise your budget, our certified gemmologists have a range of methods that can help you get the best stone for your budget. If you are looking for a 1 carat stone, for example, you could get a beautiful diamond in terms of cut, colour and clarity if you aim for a stone just under 1ct – the size difference will be negligible but the price difference considerable.

As cutters are often paid by-the-weight, they may opt to maximise size and sacrifice the cut of the stone. While a large crown, deep pavilion or thick girdle will increase the weight of a diamond, this will be at the expense of its beauty. This is why we often advise prioritising a well cut diamond over a heavier carat weight. Our goldsmiths use clever polishing and setting techniques to maximise the look of your stone anyhow, so we think the colour and sparkle are a little more important!