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    Diamond Carat Weight



    Carat Weight (one of the 4C’s) is simply the Weight of a Diamond, be it One Carat or a Half Carat. It’s all about how much the Diamond Weighs. Back in the days, Diamonds were weighed by seeds from a Carob Tree. These seeds were roughly the Weight of one Point (1 pt) to a Diamond. Since there are 100 Points in a Full Carat Diamond, there would be 100 Carob Seeds to balance it on a Scale. 


    The Diamond Scale

    Things were never exact until the Diamond Scale was invented in the early twentieth century. Now, getting the exact Carat Weight of a Diamond is easy and only takes a couple of seconds.


    But how do Carats fit in?

    • There are 100 Points in a One Carat Diamond (written as 1.00 Carat). So 1/2 Carat Diamond would simply be 50 Points or .50 Carat.
    • A 1/4 Carat Diamond would be 25 Points (.25 Carat).
    • 3/4 Carat (.75 Carat) would be 75 Points. Are you following this? It really is that easy.
    • A 10 Point Diamond is 1/10 of a Carat or 10 Points.
    • A 1.50 Carat Diamond is One Carat and a Half, or a Carat and 50 Points (150 Points in all).
    • So then when you see a .38 Carat Diamond, you’ll know it’s a little more than 1/3 Carat (.33 CT) and a little less than a Half Carat (.50 CT).
    • 58 Points is in between 1/2 and 3/4 (.50 CT & .75 CT).

    Take a look at the image below to see all the different sizes of Carat Weights




    Carat Weight Millimeter Sizes

     The Standard Millimeter (mm) sizes of Diamond Carat Weights are as follows:



    Points – Carats – Fractions

    Take a look at the chart below to see what the Points are, Carats are and Fractions are of your Diamond. Plus, see what that Carat Weight is often referred to as.



    Carat Weight and Carat Weight Total

    One thing to note here about Carat Weights is that there are different types of Carat Weights that shouldn’t be confused. If you’re looking at a Diamond Solitaire (Single Diamond), then the Carat Weight is simple; it’s the Weight of that single Diamond. But, if you’re looking at a Diamond Wedding Set, then things can change. You’ll have the Carat Weight of the center Diamond and the Carat Weight of the side stones.

    The Jeweler was giving you the Total Carat Weight of the ENTIRE ring (or Carat Total Weight written as ctw), and not the breakdown of the Center Diamond Carat Weight and the side stone Carat Weight. This makes a HUGE difference. The center Diamond could only be .33 Carat and the other .92 Carat could be in the little side Diamonds. Not good! Especially if the ring down the street had a much larger Carat Weight in the center. The point is, if they give you a Carat Weight of the ring, make sure you find out if that’s the Carat Weight of the center Diamond or the Carat Weight of the entire ring. Knowing this info can help you compare rings and prices elsewhere. Otherwise you could really be taken!


    The Same Carat Weights can look different!

    Two One Carat Diamonds put side by side can also look totally different in size as well. It’s like two people standing side by side could be the same weight, but one could be tall and skinny, the other short and fat. Diamonds are no different. From the top view, one could look 25% smaller than the other Diamond, if not more. It all depends on how the Diamond is Cut (which all depends on how much profit they can make from the initial parent rock). Things like mm sizes, Ideal Proportions and Girdle Thickness all come into play (which we will all get into with other posts). Everything is affected by Carat Weight, even the Inclusions in the stone (or more appropriately, the Clarity of the Diamond). Carat Weight affects how strictly Diamonds are graded as well. Bigger Diamonds get graded more thoroughly. Larger Carat Weights make it easier to spot Flaws and Imperfections, plus larger Carat Weights also show off the Color of the Diamond better.