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Diamond Carats Explained

One carat is equal to a weight of 200 milligrams and according to the GIA – a carat is subdivided into 100 ‘points’ which enable jewelers to give very precise measurements of the weight of a diamond stone.

When buying diamond engagement rings, if the stone is under one carat, don’t be surprised if you go through an entire conversation without hearing the word ‘carat’. Instead, the jeweler will likely describe the diamond’s weight in ‘points’ in order to give you the most accurate picture of the diamond’s weight.

For example:

A .25 carat diamond will be called a 25 pointer
A .50 carat diamond would be called a 50 pointer

Any diamond stone which weighs above one carat – its weight will be described in carats and decimals.

So for a 1.35 carat diamond engagement ring, it would be referred to as ‘one point three five carats’.


The origin of the carat: A carob? 

When it comes to diamond engagement ring buying – nothing beats a good old romantic legend. We discussed the so-called ‘love vein’ which the Romans claimed had a direct connection from the heart to the left hand, fourth finger – therefore setting in stone that it should be the

And now we bring you the legend of the origin of the carat and its links to the mystical Carob tree.

In historical times, the only way to accurately measure items was by using a balance scale. On one side you would place the item you wanted to weigh and on the other would be another item to be used as unit weights. Once the scale balances you would count the unit weights to give you the weight of the item.

And this is where the carob seed comes into the mix. It had been previously thought that carob seeds all held precisely the same weight as each other, which would make them ideal for use as unit weights.

There was also a widely held belief that a standard carob seed weighed around .20 milligrams which is exactly the same weight of one carat. So it made sense to use carob seeds as the unit weight for measuring diamond stones.

Furthermore, the word ‘carat’ also has its origins in the word ‘carob’. Carat was derived from the Italian word ‘carato’, which itself comes from the word ‘qīrāṭ’ in Arabic, which in turn comes from the Greek word kerátion – carob seed.

So while in the past the carob seed was in fact used to measure diamonds, today the use of carob seeds wouldn’t be acceptable as it turns out that there are in fact

While perhaps not relevant today, the mighty carob seed did play its part in the diamond industry and its legacy remains today with the carat measurement system.

When did the Carat become the standard measurement for diamond weight?

The carat began as the standard measure for weighing diamonds in the 1570’s. While most countries had its own ‘carat’ measurement for the diamond industry, it wasn’t until 1871 when a proposal was made for a global carat measurement.

In 1871 the Syndical Chamber of Jewellers recommended an international carat measure of 205 milligrams which was accepted only later in 1877 by the Syndical Chamber of Diamond Merchants in Paris. Then in 1907 a metric carat of 200 milligrams was proposed by the International Committee of Weights and Measures and was globally accepted, which is the standard today.


Does a bigger carat diamond mean better quality?

One may assume that the bigger the carat weight of the diamond, the more expensive it should be? Not always. Just because the weight of the diamond is bigger, it doesn’t mean that the quality is better – which is why it’s value wouldn’t increase.

If the cut is less precise, the clarity isn’t as flawless or the stone has more colour – these factors can reduce the value of the diamond – even if it’s significantly bigger.

However, if all things are equal and the cut, clarity and colour are similar – then a bigger carat will increase the price as larger diamonds are naturally rarer to find.

Magic Carat Sizes

There are some carat weighted diamonds which are known as “magic sizes” and are significantly more expensive than other diamond carats. These include half a carat, three-quarter carat and one carat. What’s so special about these carats that they are considered ‘magic’?

Not much, except that it sounds good when talking about a dazzling one carat diamond.
If you switched the one carat for a .96 carat diamond – it just doesn’t sound the same. It is literally the rounding-off of carats that can impact the value of the diamond.

At David Ashley we will always advise you on how to get the best value diamond engagement ring for your loved one and we will always recommend looking at the bigger picture. You want to purchase a beautiful, high quality diamond, not just one which happens to have a rounded carat weight.

Do you already know the diamond engagement ring you want? Take a look at our selection of stunning and exclusive diamond rings available at David Ashley today!

And remember, with years of expert experience in the diamond industry, we are standing ready at your service! Contact us at David Ashley today and we’ll guide you through the process and help you find the perfect diamond engagement ring.



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