The ceramic glass surface covering a La Cornue induction zone is built to withstand daily cooking, but it is not immune to wear, and most of the marks that show up on it over time come from how cookware is handled rather than from any problem with the hob itself.
Sliding Pans Is the Main Cause
Sliding a pan across the glass, rather than lifting and placing it, gradually wears the printed pattern on the surface and can leave fine scratches with repeated use. This is a cosmetic effect over time rather than a sudden crack, and it happens gradually enough that it is easy not to notice until the surface looks visibly duller in the areas where pans are moved most often.
Pan Choice Matters Too
Pans with a rough, pitted, or damaged base — cast iron with a coarse unfinished bottom is a common example — are harder on the glass than pans with a smooth, flat, enameled or polished base, even when both are lifted and placed carefully. Checking the underside of a pan for roughness before it becomes a regular occupant of one zone is a simple way to reduce wear without changing any habits around lifting versus sliding.
Cleaning Without Adding Scratches
Grit left on the surface from a previous spill, ground in by the base of the next pan set down on top of it, is one of the most avoidable sources of scratching. Wiping the surface clean of any debris before placing a pan, rather than after, prevents that grinding action entirely. A soft cloth and a cleaner made for glass ceramic surfaces, rather than an abrasive pad or a general-purpose scouring cleaner, protects the surface during routine cleaning as well.
What Sugar and Plastic Spills Can Do
A spill that melts and bonds to the hot glass, such as sugar or a plastic wrapper left too close to an active zone, needs to be dealt with carefully rather than scraped at aggressively once it has cooled and hardened; a dedicated glass-ceramic scraper used gently is far less likely to leave a mark than a knife or a metal utensil reached for out of convenience.
Scratches vs a Crack
Fine surface scratches and a dulled pattern are cosmetic and do not affect how the zone heats or detects a pan. A crack in the glass is a different, structural problem — one that affects the surface’s integrity rather than just its appearance — and is not something to keep cooking on while waiting to see if it gets worse.
A Simple Habit That Prevents Most Damage
Getting into the habit of lifting rather than sliding cookware, wiping the surface before setting a pan down rather than after, and keeping the surface clear of anything not actively being used to cook prevents the great majority of avoidable marks with no real change to how you actually cook.
If your induction surface has a crack rather than ordinary surface wear, a La Cornue cooktop repair visit can assess whether the glass needs replacing.