You are misinformed. There is no issue with cast iron on a glass top. As long as the bottoms of your Ian’s are flat and smooth, they will work just fine. Better yet, get an induction too. If you have fears of scratching the glass, you can put down a silicone mat on the job, and cook on top of that. Or paper towels, to keep cleanup to a minimum.

Your copper pans will not work with induction. It many many times worth it to get an induction stove. Even if you'll need several new pans. The performance is much better. Frigidaire has a lower priced unit. Bosch 800 is a bit higher.

I had to replace all my Revere pans so I could get an induction range. I haven't regretted it one bit. Just found all the pieces I needed to replace the equivalent I had with Reverware.

I'd heard that you don't use cast iron on glass but I did it anyways. There was never an issue.

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