How Hard Is A Diamond?

Have you ever wondered why we began using diamonds in jewelry in the first place? A lot of it has to do with a diamond's hardness and durability. Exactly how hard is a diamond? With a hardness of 10 on the Mohs Hardness Scale, diamonds are the hardest known natural mineral on Earth! What is the Mohs Hardness Scale? We’re glad you asked! It all goes back to a German mineralogist, Fredrich Mohs, who invented a scale of relative mineral hardness in 1812 that we still use today to grade minerals and gemstones. Let’s break down what the scale is and why we love diamonds for more than just their beauty!


What is the Mohs Hardness Scale?
When evaluating the durability of a gemstone (ability to be used in wearable art/jewelry) gemstones are measured on three things: hardness, toughness, and stability. Hardness is better defined as a stone's resistance to scratching and the Moh’s hardness scale is a relative scale that ranks gems based on their resistance to scratching. A diamond is the highest grade on the scale which is a 10, and corundum (sapphire and ruby) rank at a 9. But since the scale is relative, diamonds are many times harder than corundum.


Why does it matter / why should I care?
Determining the hardness of a stone is important when considering a stack! If you have exposed girdles and/or gemstones that are going to rub against each other in a stack it is very important to know that any number on the scale that is higher than another number can scratch the number below it. At Consider the Wldflwrs, we typically only work with gemstones with a hardness grade of 8 or higher so that our rings can be considered heirloom quality and last for generations without the fear of completely scratching the gemstone and having to replace it.


Where would lab-grown diamonds fall on the scale?
Lab-Grown diamonds are the same material as earth-mined diamonds and therefore fall into the highest hardness grade which is level 10. This cannot be said about other diamond simulants (simulants, meaning imitation diamonds) such as white sapphire (level 9) moissanite (level 9.25), and cubic zirconia (level 8-8.5).


Does the color or the diamond change where it falls on the scale?
No, the color of the diamond whether it is a white diamond, yellow diamond, blue diamond or any other fancy color does not affect the hardness grade.


Would inclusions affect this?
Inclusions (or clarity), similar to color, do not affect the hardness grade of a diamond.


What if I want to use a gemstone that falls below the hardness grade of 8?
While we typically only work with gemstones with a hardness of 8 or higher, let’s chat about what you have in mind, how often you plan to wear the piece, and your lifestyle to determine the best fit!


If you have been dreaming up an idea for a new piece of jewelry, we’d love to hear about it. Submit a Custom Bridal Application to tell us all about your style, timeline, and the gemstone you have in mind. Whatever your dreaming up, we would love to help make your dream a reality and make sure your jewelry lasts a lifetime!


References: Britannica, linked here.