4Cs - Carat Weight

Education Center

Education Center

Everything You Need to Know About Carat Weight

Different size round cut moissanite stones

Carat weight is a universal unit of measurement in the jewelry industry. Contrary to what most people think, it doesn't refer to diamond size. It refers to diamond mass (i.e. weight). 

Understanding carats can help you get a heavier, bigger-looking stone for less money. Not understanding carats leaves you open to overpaying for a scrawny, ugly-looking stone. Yes; understanding diamond weight is that important. 

Below, we'll share everything you need to know about carats. We'll cover size, price, quality, and more. Let's start with the basics.

What is a Carat?

The carat is a unit of measurement specifically for defining the weight of gemstones. image
The carat is a unit of measurement specifically for defining the weight of gemstones.

Ok, seriously, what even is a carat? No, it isn't the preferred snack of your favorite cartoon rabbit. It's a unit of measurement specifically for defining the weight of gemstones, and grown-up us thinks that's way more fun. 

The weight of a carat is precisely 0.2 grams, and here comes the rub. Mass is not the same as size. A 2ct diamond is twice the weight of a 1ct - but that doesn't mean it's twice the size. 

In other words, a carat tells you something about a diamond’s size… But not in the way you might be expecting. The relationship is loose and fluid; not directly linear. 

Carats Aren't Everything.

Gemstones vary in density and anatomy. Rubies are usually cut to be deeper than diamonds. This means a 1 carat ruby will be a little smaller than an equivalent diamond. 

This (or the reverse) is true for many other stones. Moissanite is often cut deeper than diamonds, meaning it looks smaller. Topaz is denser than diamonds, meaning it also looks smaller.

How is Carat Weight Measured?

Gemstone valuation varied from country to country until carat weight was introduced as a universal measurement in 1907.

What Does 1 Carat Weigh?

1-carat weights 0.2 grams, or 0.007 ounces. A diamond weighing 1 gram would be 5 carats. Now that's a big honkin' diamond! 

Diamonds are also referred to in points. 1 carat is 100 points and a half-carat diamond might be called a 50-point diamond. 

Where Did the Carat System Come From?

The word "carat" originally comes from carob, like the seed. 

Carob seeds have been used as a counterweight in measuring jewelry throughout history. It was thought – albeit incorrectly – those carob seeds were uniform in weight. 

Does Carat Weight Impact Price?

There are a few different factors that all contribute to the price of a gemstone. You've probably heard of those referred to as the 4 C's. Let's have a quick breakdown.  

  • • Carat: The weight of the diamond 
  • • Cut: Refers to how closely the diamond’s cut matches the perfect proportions for its shape 
  • • Clarity: Refers to the absence of inclusions and blemishes in the stone 
  • • Color: Refers to the hue of the diamond, with colorless grades like D-F being the most desirable

Note that fancy diamonds are graded on their own scale. Each of these C's, including carat, plays a part in defining a price. 

Why Some Carat Weights Cost More

Larger stones are harder to find in nature so a 1ct diamond might cost four times more than a half-carat of similar quality. 

There are also carat weights that are considered more desirable. People seek out these "magic sizes" (1ct, 0.75ct, 0.5ct, etc.), and as a result, they cost a bit more. 

Looking for a diamond that is just a bit under, i.e., 0.92ct, 0.47ct, will land you a similar size stone while saving you a fair amount of money.  


Carat weight is just that, a measurement, and it’s just one of many factors in choosing the right diamond. 

If it's the size and sparkle you're after, keep in mind that cut and diamond shape might be what you're looking for. 

If you want to save money, look for stones slightly under a full-carat / half-carat / quarter-carat.

Engagement Rings

Design your engagement ring and center stone

The Kamelie WG R

The Kamelie

View this ring
The Lenny WG R

The Lenny

The Adelle WG R

The Adelle