October 28, 2026

Can Diamonds Chip or Break? What 'Hardest Material' Really Means

By Sasha Tarasova

Filed under Antique Diamonds & Diamond CutsAntique & Vintage Engagement RingsBuying GuidesCare, Sizing & Insurance

Short answer: yes, diamonds can chip and, more rarely, break. Diamond is the hardest natural material, 10 on the Mohs scale, which means almost nothing can scratch it, but hardness is resistance to scratching, not to impact. Diamond also has four directions of perfect cleavage, so a sharp knock at the wrong angle can take a chip off a girdle, a culet or a pointed corner, or split a stone along a plane.

"Diamonds are forever" has done a great deal for the trade and very little for the diamonds. People assume a diamond is indestructible and wear it accordingly, and most online guides compound the problem by treating hardness and toughness as the same thing. They are not, and the difference explains exactly where diamonds fail, why some shapes and settings are riskier than others, and what an antique stone's century of wear tells you.

What does "hardest material" actually mean?

It means diamond resists scratching better than any other natural material: nothing but another diamond will scratch it. That is what the Mohs scale measures. Each mineral on the scale scratches the ones below it, from talc at 1 to diamond at 10. Our Mohs hardness guide sets out where every common gemstone sits.

Two things the scale does not tell you. First, it is a ranking, not a ruler: the gap between corundum at 9 and diamond at 10 is far larger than the gap between 8 and 9. Second, and more important, it says nothing about what happens when a stone is struck. Scratch resistance keeps a century-old diamond's facet edges crisp; it is no protection against a sharp blow.

What is the difference between hardness, toughness and cleavage?

Hardness is resistance to scratching; toughness is resistance to chipping, cracking and breaking; cleavage is a built-in tendency to split cleanly along particular planes of the crystal. A stone can be very hard and only moderately tough, and diamond is the classic example.

• Hardness. Diamond is supreme. This is why diamonds stay polished and why they cut other materials.
• Toughness. Gemologists rate diamond's toughness as good, not exceptional. Nephrite and jadeite jade, far softer on the Mohs scale, are much tougher because their interlocking fibrous or granular structure absorbs impact. Ruby and sapphire, at 9, have no cleavage and are generally rated tougher than diamond.
• Cleavage. Diamond has perfect octahedral cleavage: four directions, parallel to the faces of an octahedron, along which the atomic bonds are weakest. Diamond cutters have exploited this for centuries, cleaving rough stones in two with a single precise blow.

Put together, that means a diamond worn for fifty years will not scratch on a kitchen counter, but the same diamond can chip if it meets the edge of that counter hard, at speed, at the wrong angle.

Where do diamonds usually chip?

Diamonds chip at thin edges and sharp points, because that is where force concentrates and where there is least material to absorb it. In practice, almost all the chips a jeweler sees fall into a handful of places.

• The girdle. The narrow band around the widest part of the stone is the edge most exposed to knocks. A thin or extremely thin girdle, sometimes called a knife-edge girdle, is markedly more vulnerable than a medium one.
• The culet. Modern round brilliants usually finish in a sharp point at the bottom. If the stone sits low in the mount, or is stored loose, that point can chip.
• Points of fancy shapes. The tips of pears, marquises and hearts, and the four sharp corners of princess cuts, are the most chip-prone areas of any diamond. Emerald and Asscher cuts have their corners cut off, which is partly a structural decision.
• Existing inclusions. A feather, the trade name for a small fracture inside the stone, weakens it, especially if it reaches the surface near the girdle. A knock that a clean area would shrug off can extend a feather into a chip.

The common triggers are unglamorous: car doors, gym equipment, stone worktops and railings. Diamond also scratches diamond, so rings stored loose together can damage each other.

Which diamond features increase or reduce the risk?

Shape, girdle thickness, inclusions and setting decide most of the risk. This table sets out the main factors and what protects against each.

Are antique diamonds more or less likely to chip?

Old cuts have some built-in advantages, offset by a century of exposure. On the plus side, old mine and old European cuts almost always have an open culet, the bottom point polished flat into a small facet. Whatever the original intention, that facet removes the fragile point a modern brilliant carries. Old cuts also tend to have thicker girdles, often left unpolished, because cutters were saving weight from rough rather than chasing modern proportions. A thick girdle is more forgiving than a knife-edge.

On the other side, an antique stone has had decades to meet doorframes, and many have been reset more than once. It is common to find small chips or nicks at the girdle of an old mine cut, frequently hidden under a claw by a jeweler at some point in the past. That is not a reason to avoid old stones; it is a reason to examine them properly. Our guide to why antique diamonds sparkle differently explains the proportions, and the old mine cut price guide covers how condition feeds into value.

Should a chipped antique diamond be repolished or recut?

Sometimes, but not by default. The choice is between leaving the chip, hiding it in the setting, repolishing the damaged area, or recutting the whole stone, and each costs something different.

1. Leave it. A small, stable chip at the girdle that does not show face-up often does not need treatment. It is part of the stone's history and should simply be disclosed.
2. Hide it. Positioning a claw or bezel over the chip protects it and removes it from view.
3. Repolish locally. A cutter can often polish out a girdle or culet chip with a small loss of weight while keeping the stone's antique character.
4. Recut. Recutting an old mine cut to modern brilliant proportions removes much more weight and destroys exactly what makes the stone collectable. It is rarely the right decision for a good antique diamond.

Two practical points. Any repolishing changes the weight, so a stone that drops below a round number, such as from just over a carat to just under, can lose more value than the chip ever did. And an existing grading report no longer describes the stone afterwards; a new one is needed. Our guide to reading a diamond report on an antique stone explains what laboratories record, including chips, which are plotted as clarity characteristics.

Which settings protect a diamond best?

A bezel, a continuous rim of metal around the girdle, gives the most protection, because the most exposed edge of the stone is never the first thing to meet a hard surface. Half-bezels protect two sides, and V-prongs, claws shaped to wrap the tip of a pear or marquise or the corner of a princess cut, are the standard protection for points.

Bezel and rub-over settings suit active wearers and stones with thin girdles or surface-reaching feathers. Our guide to bezel-set engagement rings covers the trade-offs, including how much light a bezel admits.

A practical example is the 1.06 carat old mine cut in an 18k yellow gold bezel currently in our collection: the gold rim encloses the girdle entirely, which is why bezels have long been the setting of choice for everyday wear.

How can you stop a diamond chipping in everyday wear?

Take rings off for the activities that deliver hard knocks, store pieces separately, and have the setting checked regularly. The habits that protect a diamond are simple and dull.

1. Remove rings for the gym, gardening, moving furniture, sport and heavy cleaning.
2. Store each piece separately, in its own pouch or compartment, so diamonds cannot rub against each other or against softer stones.
3. Have prongs checked once a year, and sooner if a claw catches on clothing.
4. Clean gently. Warm water, mild soap and a soft brush are enough. Ultrasonic cleaners can aggravate feathers and loosen stones in old settings; our guide to cleaning antique jewelry sets out what is safe.
5. Know your stone. If a diamond has a large feather or has been fracture-filled, make sure any jeweler working on it knows before a torch comes near it.

What should you do if your diamond chips?

Stop wearing the piece, check the stone is still secure, and take it to a jeweler or gemologist for examination under magnification. A chip can be cosmetic or it can sit on a feather that is now more likely to extend, and only a proper look tells you which.

• Photograph the damage and note when and how it happened.
• Ask for options in writing: leave, reposition, repolish or recut, with the expected weight loss for any polishing.
• Contact your insurer before authorising work if you plan to claim. Specialist jewelry policies typically cover accidental damage, but terms vary. Our guide to insuring antique jewelry explains what to look for in a policy and why an up-to-date appraisal matters.

When should you see a professional?

See a jeweler whenever you notice a new nick, a rough spot catching your fingernail at the girdle, a stone that moves, or a claw that looks flattened. Before buying, ask the seller directly whether the stone has any chips, where they are, and whether any sit under a prong. A straight dealer will tell you, describe the girdle condition in writing, and explain whether a chip is stable. If a seller tells you a diamond "cannot chip", that is a reason to keep your money.

Questions people actually ask

Can a diamond break if you drop it?

Usually not. Most drops onto carpet, wood or tile do no damage, because the force is low and rarely lands on a vulnerable edge. A diamond can chip or, rarely, split if it strikes a hard surface at a sharp angle, especially along a cleavage direction or where a feather reaches the surface. Check the girdle and points with a loupe after any hard fall.

Is diamond the strongest material?

No. Diamond is the hardest natural material, meaning it resists scratching better than anything else, but it is not the toughest. Toughness, resistance to breaking, is rated only good for diamond because of its perfect cleavage. Jade is far tougher, and ruby and sapphire, which have no cleavage, are generally tougher too. Hardness and strength are different properties.

Can a diamond chip from everyday wear?

Yes, though it takes a real knock rather than ordinary handling. Typical causes are car doors, gym equipment, stone worktops and rings banging together. Pointed shapes, thin girdles and stones set high without protective prongs are most at risk. Removing rings for heavy work and having prongs checked annually prevents most everyday chips.

Can a chipped diamond be fixed?

Often, in the sense that a cutter can polish out a small chip at the girdle or culet, losing some weight. The stone's measurements and weight change, so it needs a new grading report. Larger chips may require recutting, which costs more weight. For antique diamonds, leaving a stable chip or hiding it under a claw is frequently the better choice.

Does insurance cover a chipped diamond?

Specialist jewelry insurance and scheduled policies commonly cover accidental damage, including chipping, but terms, excesses and limits vary by insurer. Standard home policies may cap jewelry cover or exclude certain damage. Read the wording, keep a current appraisal and photographs, and contact the insurer before any repair work begins if you intend to make a claim.

Which diamond shapes chip most easily?

Shapes with sharp points chip most easily: princess cuts at their four corners, and pears, marquises and hearts at their tips. Rounds, ovals and cushions have no points and are less vulnerable, while emerald and Asscher cuts have cut corners for the same reason. Protective V-prongs or a bezel on the points largely solve the problem.

Are old mine cut diamonds fragile?

Not especially. Old mine cuts usually have an open culet, which removes the fragile bottom point, and often a relatively thick girdle, both of which help. Their main risk is history: decades of wear mean small girdle chips are common, sometimes hidden under claws. Ask whether any chips are present, and choose a protective setting for daily wear.

Every old-cut diamond we sell is described by cut, weight and condition, and you can browse them in our old-cut diamond collection. If you want a stone found in a particular shape or setting suited to daily wear, our sourcing service handles the search and the inspection. More diamond guides sit in our diamonds archive.