Gemstone durability is a commonly misunderstood subject. Being “the world’s foremost authority on gemology,” and the source of my gemological education, of course I defer to GIA (the Gemological Institute of America) for expert advice and gem information. In this case, the subject of gemstone hardness, toughness, stability, a.k.a. gemstone durability. I have always been passionate about providing the public with practical gem advice and knowledge about the products they own and purchase, thus the reason I chose GIA education and their diploma programs.
This article from the GIA 4Cs Blog is informative, and what I especially like is the infographic showing the Mohs hardness scale. As you can see on the scale, though diamond is a 10 and corundum (ruby and sapphire) a 9, diamond is actually many times harder than a sapphire or ruby, as indicated in the sharp jump from numbers 9-10. So as you can see, the scale is not really “to scale”, but a good basic indicator of the difference in gem hardness.
Another important take-away from this article is the factors that contribute to a gem’s durability – it’s not all about hardness! Hardness measures a material’s resistance to scratching, where toughness measures a material’s resistance to breaking. My favorite analogy is one I believe I learned from a GIA instructor – leather is tough but not hard where glass is hard but not tough. You can scratch leather easily, but it is not easy to break. Glass on the other hard does not scratch as easily as leather, but it is quite easy to shatter.
From many years on a jewelry repair bench, I have always encouraged customers to understand at least a little bit about the jewelry they wear. Diamonds are not indestructible! Trust me, I have seen many a broken diamond in my time, and many a baffled customer. A little care goes a long way and I don’t recommend wearing any jewelry around the clock. Taking a closer look at the jewelry you wear frequently can help to identify when it might be in need of repair. Spotting a loose stone before it wiggles out of a setting can save you quite a bit in replacement costs, as can noticing a prong that looks worn or weak. Don’t take your beautiful jewelry for granted, being an educated and aware jewelry consumer will benefit you in the long run.