Diamonds are known for their brilliant sparkle and durability. While often considered invincible, the question of whether they can be scratched is nuanced. Understanding their scientific properties reveals their true resistance to wear.
The Science Behind Diamond Hardness
The hardness of diamonds stems from their unique atomic structure. Each carbon atom forms strong covalent bonds with four others, arranging into a rigid tetrahedral lattice. This network creates a stable and resilient structure, making diamonds the hardest known natural material.
Hardness, for minerals, refers to a material’s resistance to scratching. The Mohs scale of mineral hardness, developed in 1812 by Friedrich Mohs, ranks minerals by their ability to scratch one another. Diamonds occupy the highest position on this scale, with a rating of 10, indicating their superior scratch resistance. This means a diamond can scratch any material with a lower Mohs rating.
What Can Scratch a Diamond
Despite their exceptional hardness, diamonds are not impervious to scratching. The only material capable of scratching a diamond is another diamond. This is because only a material of equal or greater hardness can abrade another. Consequently, diamonds are often cut and polished using diamond-tipped tools or diamond dust.
Everyday items like steel, glass, or other common gemstones are softer than a diamond and cannot scratch it. However, specialized industrial applications use materials nearly as hard or harder. For instance, synthetic diamonds or ultra-hard materials like cubic boron nitride are used in cutting and grinding tools. For typical daily wear, the risk of scratching a diamond from household materials is negligible.
Caring for Your Diamonds
Given their exceptional hardness, proper care for diamonds involves preventing them from scratching softer jewelry. Storing diamond pieces separately from other gemstones and precious metals, in individual soft pouches or jewelry box compartments, helps avoid damage to other items. This also prevents diamonds from scratching each other when multiple diamond pieces are stored together.
While diamonds are resistant to scratching, distinguish hardness from toughness. Hardness relates to scratch resistance, but toughness describes a material’s ability to resist breaking or chipping from impact. Diamonds possess perfect cleavage, meaning they have specific planes along which they can split if struck with sufficient force, despite their overall hardness. While a diamond will not scratch easily, it can still chip or break under a sharp blow. Cleaning diamonds typically involves mild soap and water with a soft brush, ensuring the setting is also safely maintained.