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Guide to Diamond Carat

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When you’re buying a diamond, carat is one of the most important aspects to consider. Hi, I'm Brian with B2C Jewels. In this video, I’m going to simplify what diamond carat is all about.


Diamond carat refers to the weight of the diamond. One carat is equal to 200 milligrams or 1/5th of a gram. 5 carats would be equal to 1 gram. So, more carat, means more weight and this is why diamond prices go up as the carat weight increases. Sometimes, people confuse carat with measurements of size. There is of course a correlation between the carat weight of a diamond and its sizebut the carat weight can be distributed in many different ways.


To understand this, let's look at a round brilliant diamond. When you see it face-up, only the top is visible.This is known as the spread of the diamond. The diameter or width of this spread is often what people are referring to when they think about size. Diamonds of the exact same carat weight likely will nothave the same diameter. The spread of a diamond depends on the cut. A deep cut diamond like the one on the left will have a smaller diameter, while a shallow cut diamond like the one on the right will have a bigger diameter, though they could both have identical carat weight.


So when you're buying a diamond, you want to know how big or small it will look when it is on a ring on her finger. Well, there is an average size chart that you can use as a guide for expected size vs. carat.


A 0.25 carat diamond will have an average diameter of 4 millimeters, a half a carat diamond should measure about 5 millimeters, a 0.75 carat diamond at 6 millimeters and so on.


Also remember that peripheral factors play a big role in the appearance of a diamond. The fingersize, the setting of the ring, the size of the band, etc. all affect the perceived size of a diamond. We always recommend trying on rings to figure out the best carat weight. B2C Jewels has a try at home service that lets you try replica rings at home. You can find out more about that on our site, but let's talk about carat and price correlation.


The price of a diamond is a result of all the 4Cs and not just the carat – so all the other factors being equal, the price of the diamond goes up as the carat weight increases. Another factor to remember is that the price does not increase proportionally.  Bigger diamonds are rare and so they cost more per carat, meaning a 3 carat diamond will be substantially more than 3 times the cost of a 1 carat diamond. But, there is a way to save while still getting the carat weight that you want.


Diamonds carat weights such as 0.50, 0.75 and 1 carat are called benchmark or “magic” weights. Most people want to hit these benchmarks of 1 carat or 1 ½ carats so the price jumps up demand increases.  If you can find a diamond just under these benchmark weights, say a .9 carat, or a 1.40 carat you can save substantially.  The difference in physical size will be minimal, but the difference in price could be substantial.


Remember to visit to buy the beautiful diamond of her dreams with these tips.