Understanding the 4 C's of Diamond Grading...there's a Fifth C
Color, Clarity, Carat Weight, Cut. These are the Four C's when buying diamonds. But there's another factor that also influences price: shape. (There does' seem to be a good synonym for shape that begins with the letter 'c').
Color: graded in a letter scale that begins with D, known as "colorless" and falls to Z. Somewhere around J there begins to be a "warm" quality to the stone as it is getting noticeably yellow. Not, NOT, fancy color yellow, but off-color yellow. Fancy yellow will look like a canary, yellow like a chemically charged old banana peel.
Clarity: graded from Flawless to a scale that combines letters and numbers: Very Very Semi-Imperfect subset 1 (VVS1) to VVS2, then VS1, VS2, S1, S2, I1, I2, I3. Go ahead and substitute the word 'industrial' for 'imperfect' when you get down to the bottom, not as a jewelry snob, but because the stones are usually a visual mess. Before modern "marketing" these were ground up for industrial use.
Carat Weight: Size does make a difference. As the size goes up the price goes up at an exponential rate. Carat weight is based on the decimal system. One hundred points in a carat, one hundred pennies in a dollar. 50 points has the same meaning as half a carat and is written as 0.50 carat.
Cut: Cutting, or rather, faceting, a diamond is a mathematical equation that has evolved over time. Any error can affect the appearance and/or the sparkle of the diamond. There are various effects that are named, like "fisheye" or "thick girdle" or "shallow cut." If the last facet, the cult (pronounced cue-lette), is cut too big then it stands out like a big black dot when you look at your diamond.
Shape: Sometimes included in Cut, but shape stands on it's own because it also affects price. Given the availability on the market of certain shapes, the price will rise and fall on that factor alone.
Photo: Pelican Diamond Ring Custom Designed and Handmade by Lisa Voelker and Tom Owczarzak of Jan David, Inc (All Animal Jewelry, Jan David Design Jewelry, Tosa Fine Jewelry)