Diamond Sparkle - This is where the magic happens.

I like to use one word to describe the beauty of a diamond and that is sparkle. Diamond sparkle is something that everybody can understand. Gemologists use words like fire, scintillation, light return, and spread. I will stick with sparkle because that is what you are paying for in a great diamond.

The basics of how a diamond works is pretty simple. It captures light that enters the diamond and then refracts the light back out the top of the diamond and into your eye. It also has a prism effect in separating the white light that enters into a spectrum of colors.

A diamond can do this so well because it has the amazing ability to slow light down to about half its normal speed. No other clear object can do that. This fact also means that light will not leave a diamond until it hits a face at close to a 90 degree angle. So once light enters a diamond it bounces around like a hall of mirrors until it hits a face just right to escape. Hopefully that is the top face (table) so it can shine in your eye and sparkle.

What can cause that not to happen?

If the diamond isn't cut right then the light will be able to escape through all sides and the little bit of light that actually does make it back out the top will look dim. A good diamond will reflect almost all the light that enters the diamond out the top. This can only happen if the diamond is cut correctly.

lightpath

Contaminates inside the diamond can also absorb some of the light that is bouncing around inside and cause it not to leave the diamond. These are technically called inclusions and are measured in the clarity category

The symmetry of a diamond can also decrease the diamond's sparkle. Symmetry is just that, how symmetrical is the diamond. Do the facets on the top of the diamond match with the facets on the bottom of the diamond? If they don't then you will lose some of that light and sparkle.

For the most beautiful diamond, look for a symmetry grade of ideal (ID), excellent (EX), very good (VG), or good (G) for an AGSL graded diamond, and excellent (EX), very good (VG), or good (G) for a GIA graded diamond.

The next factor is polish. This is just like the paint job on a car. If the paint is good but it is not polished well it won't look as good as it could. Vise versa, if it isn't the best diamond but has a good polish it can help the diamonds appearance. Polish technically refers to the smoothness of the diamonds facets. If they aren't smooth the diamond will look hazy or dull.

Lastly diamond color can affect the sparkle. To have the best sparkle a diamond needs to look clear. If the diamond is not clear then some of the colors of light will be absorbed by the diamond thus giving it a yellow look. Diamond color is graded from D (clear) to Z (yellow). Price obviously changes as you get closer to D. Many people agree that G is the best value you can get. D, E, and F are considered colorless. This leaves people to believe that G looks yellow. If you put a D next to a G you might be able to see the difference but seen on it's own you will not be able to notice.

So, how to put it all together. Good question

Buying a diamond requires compromises. Where those compromises come from are up to you. For most people money will limit their choices. It is all one big balancing act. My advice would be to focus on the cut first and foremost. Get the best cut you can afford in the size you want and then balance out the color, clarity, polish and symmetry. In the end if you make the decision on these factors from an educated perspective you will feel extremely proud and confident that you bought the best diamond your money could buy and were not just sold some diamond in the window that was on sale.

Next: Diamond security

Shape | Size | Spending | Sparkle | Security