Dirty Diamonds

A dirty diamond knows no class.


Regardless of what anybody tells you, the maximum weighted light return (also known as flux density) for any diamond, in any shape, is 91 Brisance Luminosity Rating (or BLR) –Class 1; A.G.S.000; American Ideal; Kaplan; 8-Star; or Hearts on Fire, 91 BLR is all you get. In the end, mathematician Tolkowsky’s numbers for rounds hold up and mathematician R.W. Ditchburn, PhD, proved in his monumental book Light that the same concepts could be applied to any shape diamond. In simplistic terms, you need three things to appreciate the sparkle of a diamond:


1. An observer
2. A diamond
3. A light source


Remove any one and you’re left pondering, “Does a tree that falls in the forest make a sound if there is no one there to hear it?”, or better said, “How much beauty can a diamond possess in the dark and how well-received can a diamond be if it is never viewed?”


I’ve spent the better part of my adult life helping people critique, evaluate, and eventually choose the best diamond for them. With each passing day, the diamond buying public is becoming savvier. However, many of you are buying magnificent diamonds cut from full-term rough (NOT macle or flat rough) and allowing them to gather so much soot, dirt, oil, hand lotion, soap, hairspray, and grease that any benefit from buying a well-proportioned, white, eye-clean, gigantic rock is negated. Please remember this fact: A dirty diamond knows no class! Repeat it again: A DIRTY DIAMOND KNOWS NO CLASS! It doesn’t make a difference whether you have a well-proportioned Class 1 or a poorly proportioned Class 4 if you don’t keep it clean. If you as the wearer of a new diamond aren’t prepared to religiously clean your diamond every day, day-in and day-out, then throw my book away or anybody else’s book that you have read on diamonds! It won’t make one bit of difference what clarity or color grade you have if you don’t keep it clean! And I’m not talking once-a-week clean or clean-it-when-it gets-dirty clean, I’m talking EVERYDAY clean! Take 60 seconds of your day to drop your ring in an ultrasonic cleaner or clean it with an ultrasonic toothbrush. If you’re not willing to do that, you’ve flushed a lot of money away.


If you’re a man reading this and you’re about to plunk $15K down for a 1 carat diamond and you know your fiance to be a person who can’t keep her own car clean much less a new diamond clean, then stop!! Re-evaluate your purchase. If the only benefit of a good diamond is amplified light return (when clean), then don’t purchase a good-quality diamond if the diamond can’t be properly maintained. At the end of any given day, even the 91 BLR diamonds will drop to 61 BLR due to the oil and dirt that accumulates from normal wear. Within a week, the diamond will look as if a tropical depression has moved in, hazy and foggy with poor visibility. For off-makes (or poorly proportioned stones) the effect is more rapid; within 2 weeks it’s lifeless city! But in the end, if neither the cheap, half-price from a macle or flat Class 4 nor the expensive, sparkly dynamo is cleaned, they will look the same!


I tell my clients every day that a great diamond is like a battery-operated toy at Christmas: it’s fun and exciting as long as you’ve got working batteries in the toy. Allowing a diamond to get dirty is like removing the batteries from the toy. Please keep your diamonds clean, and if not, trade them in for crummy ones and pocket the savings.


Remember: A dirty diamond knows no class.


The Diamond Guy


by Fred Cuellar, author of the best-selling book “How to Buy a Diamond.” More questions? Ask the Diamond Guy
The founder and president of Diamond Cutters International, Fred Cuellar is one of the top diamond experts in the world, as well as a three-time Guinness Book record holder in jewelry design.
Fred Cuellar
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