Diamonds possess a remarkable reputation for their exceptional hardness, often considered the strongest natural material. While diamonds are highly resistant to scratching and wear, they are not impervious to all forms of damage. Certain forces and conditions can compromise their integrity, leading to chips, fractures, or even complete destruction. Understanding these vulnerabilities provides a clearer picture of diamond durability.
The Science of Diamond Hardness
Diamond hardness stems from its unique atomic structure. Each carbon atom bonds strongly to four others in a repeating tetrahedral arrangement. These strong covalent bonds form a robust three-dimensional network. This specific arrangement, known as a diamond cubic crystal structure, creates a material highly resistant to scratching and abrasion. The uniformity and strength of these bonds contribute significantly to diamond’s position as the hardest natural substance on the Mohs scale.
This structural rigidity means a diamond resists scratching by almost any other material. However, hardness differs from toughness, which is a material’s resistance to breaking or fracturing under impact. While diamonds excel in hardness, their crystalline structure also makes them susceptible to other types of damage. The directional nature of their bonds, despite their strength, plays a role in how they can be affected by specific forces.
How Diamonds Can Be Damaged
Despite their hardness, diamonds are brittle, meaning they can break under sufficient impact. This vulnerability stems from their distinct cleavage planes, natural lines of weakness within the crystal structure. A sharp blow along one of these planes can cause a diamond to split or fracture cleanly. Diamond cutters use this to shape rough diamonds.
Diamonds are also susceptible to damage from extreme heat. As pure carbon, diamonds can burn or oxidize when exposed to high temperatures in the presence of air. This combustion typically occurs at temperatures around 800 to 900 degrees Celsius (approximately 1400 to 1650 degrees Fahrenheit). At these temperatures, the carbon atoms react with oxygen, transforming the diamond into carbon dioxide gas, leaving no ash or residue. In the absence of oxygen, diamonds can transform into graphite, a more stable form of carbon, at high temperatures.
While diamonds are highly resistant to most chemicals, certain aggressive substances can affect them. Strong oxidizing agents or industrial acids can react with the carbon atoms, particularly at elevated temperatures. Though uncommon in everyday situations, this shows diamonds are not immune to chemical alteration under extreme conditions.
Debunking Common Myths About Diamond Vulnerability
A common misconception is that diamonds can be damaged by household acids. However, common acids do not harm diamonds because their tightly packed carbon atoms are largely non-reactive to them at room temperature. The diamond’s robust atomic structure provides strong resistance to most chemical interactions.
Another myth suggests that if a stone can scratch glass, it must be a diamond. While diamonds, with a Mohs hardness of 10, can easily scratch glass (which is typically around 5.5 to 7 on the Mohs scale), many other materials can also scratch glass. Therefore, a glass scratch test alone is not a definitive way to identify a diamond.
The idea that dropping a diamond will cause it to shatter is largely a myth, although not entirely without basis. Diamonds are brittle and can chip or break if they sustain a strong, precise impact, especially on a cleavage plane or a vulnerable point like the girdle. However, minor everyday drops onto softer surfaces are unlikely to cause damage due to the diamond’s overall strength.
Ultimately, the belief that diamonds are completely indestructible is inaccurate. While they are exceptionally hard and durable, they possess specific vulnerabilities to impact, extreme heat, and certain harsh chemicals. No material is truly invincible, and diamonds are no exception.
Protecting Your Diamond
To prevent damage, avoid wearing diamond jewelry during activities involving potential impacts. This includes sports, heavy lifting, or tasks where the jewelry might strike hard surfaces. Such precautions minimize the risk of chipping or fracturing the diamond along its cleavage planes.
Protecting diamonds from extreme temperatures is also important. Remove diamond jewelry before exposing it to significant heat sources, such as open flames or very hot ovens. Prolonged exposure to high temperatures can potentially alter a diamond’s color or cause internal inclusions to become more visible.
Proper storage also safeguards diamonds. Storing diamond jewelry separately from other pieces, ideally in a soft-lined box or individual pouches, prevents scratching of softer metals or other gemstones. This also protects the diamond itself from accidental impacts with harder objects.
Regular professional cleaning and inspection are beneficial for maintaining a diamond’s integrity. A jeweler can check for any loose settings that might expose the diamond to damage and identify minor issues before they worsen. This proactive approach helps ensure the longevity and beauty of your diamond.