I had to look up at what temperature diamonds start to oxidize/burn[0]: Different sources say different things but apparently it's somewhere between 700°C and 900°C (depending on the exact conditions I suppose).

I suppose that's enough for cookware?

[0]: https://m.youtube.com/watch?v=TPyuDY3iq1Q

Your lower and is around the melting point of aluminum, that is in wide use in cookware.

Gas flames are easily hotter and exposure to flame can start burning below the autoignition temperature.

Maybe it could be used as an inner-layer in multi-layer cookware (like some pans use aluminum today)?