Hi, I'm Craig. My large forehead sparkles like a diamond, and this is Mental Floss on YouTube. Today I'm going to answer butterwit's big question: why are white diamonds so expensive? Well Mr. butterwit, a few things determine a diamond's quality, therefore its price. These are what the diamond experts refer to as the four C's: color, cut, clarity, and carat. There's a fifth option though which is 'Craig'. You asked specifically about color, but I'm gonna tell you a little bit about all of them, because all four effect a diamond's cost. Let's get started. 

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Okay, listen up fellas, I just proposed to my girlfriend and buying the ring was the hardest part. This is important. A diamond's cut refers to how symmetrical and well polished the diamond is. This is important because it determines how light reflects off of the diamond. Unlike the other C's, diamond cut doesn't have a standardized grading scale. Some of the most popular ones are the round cut, oval cut, princess cut, Mario, Luigi, and Toad. Currently round cut diamonds are more pricey because they're popular and more expensive to make. So if you choose a white diamond in a different cut, it will be less expensive.

A diamond's clarity determines if it has blemishes, cloudiness, cracks, and so on. This is the diamond's clarity scale. If the diamond has scales on it, you got that diamond from a dragon and I salute you brave Sir or Madam. Ideally the diamond is flawless if you can't see any of that stuff under ten times the magnification. The higher the clarity, the more rare and expensive it is.

Moving on to carat, which describes a diamond's mass. One carat equals 200 mg. A diamond with a higher carat is more expensive. Are you starting to see a pattern here?

As for color, it has a scale as well. A white diamond is known as colorless, which is ideal on that scale. Why? Well let me through a fifth C at you, carbon. I threw Craig at you earlier, but that's not real. Diamonds are completely made up of carbon. A white diamond is pure carbon, which means it has no impurities. And then that means it's more expensive. Most of the diamonds that are found fall lower on the color scale, with a yellow or brown tint to them. This is nitrogen and even a small amount of it can change the color making the diamond impure. Once you go beyond Z on that scale you reach what is known as "now I know my ABCs" - no - fancy colored diamonds. As you probably know, some of the most expensive diamonds in the world are pink, red, and blue. The dark blue Hope Diamond is worth over two hundred million dollars. That's simply because these diamond colors are more rare and more expensive.

Thanks for watching Mental Floss on YouTube made with the help of these lovely diamonds. If you have a question of your own that you would like answered, such as "Will you marry me?", leave it in the comments below. The answer to that one is no, I'm already getting married. Sorry about that. See you next week.