It is the elements which cause the colorful of the diamonds, but not all the diamonds are suitable for this rule, the microelements the colors of the natural yellow diamond and the blue diamond; it is the nitrogen that made the yellow while the boron made the blue diamond. However the other diamonds are different from those two, they form because of the defect of the lattice.
The diamonds without any other colors and the purer the better, in the jewelry industry there seem a rule that the diamonds without motley cost more expensive the one with. In reality, the motley affects the main color of the diamonds in a certain extent.
Both the colored diamonds and the white diamonds should take the 4C standard into consideration, indeed the colored diamonds are belong to diamonds. Because of the “color” the colors are the most important on the standard.
Compare with the misunderstanding three, it isn't hard to see that the weight isn't so that important according to the diamonds but the colors. So if you want to invest them you should firstly take over the colors of the diamonds. Diamonds in the same weight, the darker the color the valuable to invest, the diamonds with heavy weight but the color isn’t good enough then the diamonds value are not as good as the small one. Ask the Jewelry Optical Glass Magnifier so that you can see it clearly the colors of the diamonds if you are planning to buy diamond jewelry.