Diamond Carat Weight

To put it simply, diamond carat weight measures how much a diamond weighs. 

A metric “carat” is defined as 200 milligrams. Each carat is subdivided into 100 ‘points.’ This allows very precise measurements to the hundredth decimal place. A jeweler may describe the weight of a diamond below one carat by its ‘points’ alone. For instance, the jeweler may refer to a diamond that weighs 0.25 carats as a ‘twenty-five pointer.’Diamond weights greater than one carat are expressed in carats and decimals. A 1.08 carat stone would be described as ‘one point oh eight carats.

All else being equal, diamond price increases with diamond carat weight because larger diamonds are rarer and more desirable. However, two diamonds of equal carat weight can have very different values (and prices) depending on three other factors of the diamond 4Cs: Color, Clarity, and Cut.

While now you know what carat means, it’s also important to remember that a diamond’s value is determined using all of the 4Cs, and not just carat weight.

How did the carat system start?

In order to understand what a diamond carat measures, it would help to know the origins of the modern carat system. Carat weight started with the carob seed, when early gem traders used the small, uniform seeds as counterweights in their balance scales. Today, the carat is the same milligram weight in every corner of the world.

What are “magic sizes”?

Some weights are considered “magic sizes” – half carat, three-quarter carat, and carat. Visually, there’s little difference between a 0.99 carat diamond and one that weighs a full carat. But the price differences between the two can be significant.

Alex H.
David was incredibly professional got my ring done ahead of schedule. I had been looking for somebody to make me an engagement ring for some time and felt pretty uncomfortable dealing with many of... the jewelers I had spoken with. Fortunately for me I stumbled into David's shop and he walked me through all the steps and made the process super comfortable. He listened and was receptive to what I asked for in a ring, and my god did he deliver. I would recommend David Stern 10/10 times and I look forward to doing all of my future business with him.read more
Paul G.
A hidden gem of a jewelry store and apprasier. I truly felt that I could trust them and get accurate valuation of jewlery and recommendations for future jewelry. They were responsive to questions... and phone calls. Highly recommend.read more
Kathi V.
I lost the diamond in my custom designed wedding ring when the setting prongs became loose without me realizing. I was beyond heartbroken and sad and it actually took me 4 years to look for a jeweler... that I could trust to help me. My original setting was too high and I thought I would have to have the ring completely redesigned. After a diligent search , I found David Stern Jewelers. David was very welcoming and entering his store felt more like visiting an old friend than a stuffy, uptight establishment that most jewelry stores feel like (to me, anyway). David assured me that we could lower the setting and he had a beautiful pear shaped diamond that fit perfectly. And, amazingly enough, he had the new diamond in the new setting within 3 hours! I'm so happy that I walked into that little "gem" of a store and met David! He's the real deal!read more