As the title says....never had one before, it's been in about a month. It looks badly scratched or marked but doesn't look like food stains, it's on the centre zone. DH reckons its from a cheap wok pan I bought but the pan itself is totally smooth on the bottom. I'm really worried about how to try and get it off, have tried kitchen and glass spray and rubbing with a plastic spatula and cloth. Anyone else had this and can advise? I assumed they'd be a bit more durable. Is it worth me ordering the manufacturers cleaning and glass scraper kit?