What is this white residue?

[Wildflowers99]

Quite often when I cook something on the hob these marks are left, even when the hob is clean and the pans are fresh from the dishwasher (dry). What is it? Such a small thing but it’s really annoying me! Thanks

Bump! Sorry it’s so banal and everyone was probably expecting something about cocaine 😂😂

Is it an induction hob? How old?

Could it be a bit of moisture you haven't noticed?

Could moisture do that? Yes it’s an induction hob, already there when we moved in but guessing it’s about 10 years old.

My hob is electric and not induction- yes any water tends to burn into a white powder on my hob, and I don't always notice it before I start cooking.

Might be different with induction though.

Do you have hard water where you are? I could imagine if the water is particle heavy it might leave a noticeable residue.

Wondering if something within the glass has broken down. Or is it on the surface and wipeable?

Google says could be mineral deposits from hard water caused by high heat. I have a dull area on mine . It’s matt whereas the rest is shiny. I think it got scorched once and won’t come off. Didn’t think that was possible.

I'd imagine it's just mineral deposits from water droplets that have evaporated leaving behind the minerals. As they won't evaporate.