There’s a particular frustration that comes with looking down at your wrist and noticing a scratch across the crystal of a watch you love. Doesn’t matter if it’s a £150 dress watch or a piece you saved up for over two years — that mark makes the whole thing feel diminished. Like a chip in a wine glass. You know it’s still functional. You just can’t stop looking at it.
The good news is that a surprising number of watch crystal scratches can be sorted at home, without sending your watch off to a watchmaker and waiting three weeks for it to come back. The key — and this is the part most people skip — is knowing what kind of crystal you’re working with before you pick up a single cloth or compound. Get that wrong, and a minor surface scratch becomes a much more expensive problem.
Watch crystals come in three types: acrylic (plastic), mineral glass, and sapphire. Each scratches differently and responds differently to treatment. This guide covers all three.
Identify your crystal type before you begin
Before you do anything, put the polish down and spend five minutes working out what your crystal is made of. This is the single most important step in the whole process, and skipping it is how people accidentally make things worse.
Acrylic crystals — sometimes called Hesalite or plastic crystals — were standard on most watches through the mid-twentieth century and still appear today on vintage-style pieces, field watches, and more affordable everyday timepieces. They scratch easily but are also the easiest to restore. If your watch was made before the 1980s, there’s a decent chance it has an acrylic crystal.
Mineral glass crystals are the most common type on modern mid-range watches. Harder than acrylic, more scratch-resistant, and slightly cooler to the touch. They can still scratch — it just takes more effort, and fixing those scratches takes more work too.
Sapphire crystals are what serious mid-range and luxury watches use — Rolex, Omega, TAG Heuer, and many others. Synthetic sapphire rates 9 on the Mohs hardness scale, so scratching it during normal daily wear is genuinely rare. What often looks like a scratch on a sapphire crystal is more likely surface grime, a micro-abrasion in the AR coating, or a mark left by something even harder — a diamond or a ceramic composite.
How to tell them apart at home
The fingernail drag test: Run your fingernail gently across the surface. If it catches and you can feel the scratch as a distinct ridge, that points to acrylic. Mineral glass and sapphire scratches are shallower — your nail typically glides over them.
The tap test: Gently tap the crystal with your fingernail. Acrylic gives a dull, slightly hollow sound. Mineral glass and sapphire give a crisper, harder sound, like tapping a drinking glass.
The temperature test: Sapphire and mineral glass feel noticeably cool against your cheek or the inside of your wrist. Acrylic warms up quickly. Not a perfect test on its own, but useful combined with the other two.
Still unsure? Check the manufacturer’s website or the documentation that came with your watch. Most reputable brands list the crystal material in their product specs.
This matters because using the wrong treatment on the wrong crystal — applying an aggressive abrasive to sapphire, for instance — can damage the anti-reflective coating or create marks that weren’t there before. Identify first. Everything else follows from that.
Tools and materials you’ll need
Most of what you need is already in your bathroom cabinet or is cheap to pick up.
- Non-gel, non-whitening toothpaste — a mild abrasive that works on acrylic. Regular white toothpaste is ideal. Gel and whitening formulas contain different compounds that can do more harm than good.
- Metal polish (Brasso or similar) — for mineral glass, where toothpaste won’t cut it.
- Cerium oxide powder — a jeweler’s polishing compound that works on mineral glass and, in some cases, sapphire. Available from watch supply retailers and Amazon. Mix with a few drops of water to form a paste before use. Usually under £10 and lasts through multiple uses.
- Diamond polishing compound — for attempting to address marks on sapphire. Paste or syringe form, from specialist watchmaking suppliers.
- Jeweler’s rouge — a fine polishing compound, sometimes used as an alternative to cerium oxide.
- Microfiber cloths — for application and buffing. Keep several clean ones on hand. Paper towels leave micro-scratches.
- Painter’s tape — to protect the bezel, case, and surrounding metalwork.
- Cotton swabs — useful for small areas or tight edges near the bezel.
- A soft-bristled toothbrush — for cleaning the crystal before you start.
- Clean water — for rinsing and mixing compounds where needed.
One thing before you start: polishing compounds and water can get into the case if you’re not careful, potentially damaging the movement or compromising water resistance. Use painter’s tape liberally around the crystal edges, cover as much of the bezel and case as is practical, and keep the watch face-up throughout. Use small amounts of product at a time.
Removing scratches from an acrylic crystal
Acrylic is the most forgiving crystal to work with. The material is soft enough that mild abrasives can genuinely level out surface imperfections. For a vintage piece or a daily wearer that’s accumulated some wear, this process can produce a result that’ll surprise you.
Step 1: Clean the crystal
Dampen a soft-bristled toothbrush and gently scrub the crystal surface to remove dust, grime, and oils. Rinse and dry with a microfiber cloth. You want to polish the crystal itself, not grind particles of dirt into it.
Step 2: Tape off the bezel
Apply painter’s tape carefully around the edge of the crystal, right at the boundary between the crystal and the bezel. Take your time here — this is what stands between your compound and the case finish.
Step 3: Apply the compound
Squeeze a pea-sized amount of non-gel white toothpaste onto a clean microfiber cloth or cotton swab. Toothpaste genuinely works on acrylic — the abrasive particles are mild enough to polish without causing damage. A dedicated plastic polish like Novus No. 2 gives slightly more controlled results if you have it.
Step 4: Buff in circular motions
Using light to medium pressure, work the compound into the scratched area with small, circular motions. Keep the movement consistent. You’re polishing, not sanding — don’t press hard. Work for 30 seconds to a minute, then wipe away the residue with a clean section of cloth.
Step 5: Assess and repeat
Check the crystal under good light — natural light near a window is ideal. You should see some improvement already. Light surface scratches often need only one or two passes. Deeper scratches may need three to five rounds, with a wipe-down and inspection between each.
At some point, you’ll hit diminishing returns. The scratch is either gone, reduced to the point where you can’t notice it, or it’s clear it’s too deep for surface polishing to fix. Over-polishing an acrylic crystal can thin the material and create haziness that’s harder to deal with than the original scratch. Know when to leave it.
Step 6: Final clean and tape removal
Rinse with clean water, dry with a fresh microfiber cloth, and carefully remove the tape. The crystal should look noticeably clearer than when you started.
Removing scratches from a mineral glass crystal
Mineral glass is harder than acrylic, which means its scratches take a more abrasive compound and more patience to address. Toothpaste won’t do anything useful here.
Step 1: Clean and prepare
Wipe the crystal thoroughly with a damp microfiber cloth to remove dust, oil, and residue. Dry completely. Apply painter’s tape around the bezel.
Step 2: Choose your compound
For light-to-moderate scratches, metal polish like Brasso works well — apply a pea-sized amount on a microfiber cloth. For more significant scratches, mix cerium oxide powder with a few drops of water to form a thick paste. It polishes glass without being overly aggressive, which is why watchmakers and restorers reach for it first.
Step 3: Apply with controlled pressure
Work the compound onto the scratched area using firm, circular motions. You need slightly more pressure than you’d use on acrylic, but keep it controlled. Focus on the affected area rather than buffing the whole crystal.
Step 4: Work in small sections
If you’re dealing with multiple scratches or a larger area, tackle it in sections. Better control, easier to track progress.
Step 5: Rinse and check between passes
After each polishing round, rinse with clean water and dry with a fresh cloth. Residue can mask how much progress you’re actually making — remove it before you decide whether to continue.
Step 6: Repeat and assess
Plan for a minimum of three to five cycles before you draw conclusions. Mineral glass needs more passes than acrylic. Light surface scratches should reduce noticeably. Scratches deep enough to feel with your fingernail may only partially improve, and that’s often the ceiling for home treatment.
If after six to eight cycles the scratch looks largely unchanged, stop. Continuing will just remove more material than necessary. A watchmaker with proper equipment can polish the crystal correctly or replace it — mineral glass is inexpensive to replace, and that’s often the smarter call for serious damage.
Removing scratches from a sapphire crystal
True scratches in a sapphire crystal are rare and, honestly, difficult to remove at home. The material is so hard that most of what looks like a scratch is actually surface dirt, a micro-abrasion in the anti-reflective coating, or a mark left by something harder still — a diamond or certain ceramic composites.
Try cleaning the crystal first with a damp microfiber cloth and a drop of mild dish soap. Check under good light. What you thought was a scratch may disappear entirely. This happens more often than you’d expect.
If the mark persists:
Step 1: Clean and tape off
Same preparation as the previous sections — clean the surface, dry it completely, apply painter’s tape around the bezel.
Step 2: Try cerium oxide first
Mix cerium oxide powder with water to form a paste, then apply it with a microfiber cloth. Work in light circular motions for 30 to 60 seconds. This won’t remove a true scratch from sapphire, but it can address very fine micro-abrasions and improve overall clarity.
Step 3: Diamond polishing compound for stubborn marks
If cerium oxide has no effect, a 0.5–1 micron diamond polishing compound can theoretically work on sapphire. Apply a tiny amount to a microfiber cloth and work with very light pressure over the affected area. Be warned: this is slow, labor-intensive work, and the improvement on deeply scratched sapphire is often modest at best.
Step 4: Know when to stop
If your watch has a sapphire crystal, is worth anything significant, and has a genuine scratch — stop experimenting and take it to a professional. Watchmakers with proper polishing equipment can resurface a sapphire crystal without distorting the optics. A replacement is more expensive than mineral glass, but it’s still a reasonable option compared to DIY that may damage the AR coating or worsen the appearance.
A scratch on a Rolex Submariner or an Omega Seamaster is not a home project. There’s no shame in admitting that.
Preventing scratches going forward
A few habits make a real difference.
Store your watches properly. A watch rolling around in a drawer will pick up scratches. Use a watch box with cushioned compartments, or a soft watch roll for travel. Keep watches separated — contact with other watches or jewelry during storage is one of the most common causes of crystal scratches.
Consider a crystal protector film. Thin adhesive films designed for specific crystal sizes are nearly invisible when applied correctly and absorb minor abrasions without touching the crystal. Worth it for acrylic and mineral glass on daily wearers.
Take it off for high-risk activities. Gardening, carpentry, moving furniture, contact sports — these are where crystals get scratched. The watch adds nothing to those activities. Two minutes to remove it eliminates the risk.
Clean your watch regularly. A wipe with a microfiber cloth after daily wear removes grit, dust, and metal filings that act as abrasives when the crystal contacts surfaces. Thirty seconds. Makes a real difference over time. For a more thorough approach, see our guide on how to maintain and clean your favorite watch.
Get it serviced periodically. For valuable pieces, a service every three to five years covers more than the movement. A good watchmaker will assess the crystal, check gaskets, and test water resistance — all of which degrade over time regardless of how careful you’ve been.
Be mindful when layering jewelry. Bracelets and bangles worn alongside your watch can graze the crystal repeatedly throughout the day. If you wear both, take care with how they sit together — there’s more to it than most people think when it comes to how to layer bracelets with your watch without scratching it.
One last thing
Identify your crystal type first, match your method to what you’re actually working with, and be patient. Most surface scratches on acrylic and mineral glass can be significantly reduced or eliminated without incurring any professional service costs. There’s a real satisfaction in doing that yourself.
But know your limits. Deep scratches, AR coating damage, and genuine marks on a high-end sapphire crystal are situations where a professional is the right call — not because it’s beyond you in principle, but because getting it wrong on a watch worth real money costs more than getting it right. Sometimes, taking it to a watchmaker is the most competent thing you can do.
