The other night I cracked my cast iron pan. I have to admit I haven’t always taken the best care of the pan, but I always heard cast iron is nigh indestructible and seen 100 year old pans with rust and pockmarks come back to brand new and shiny, so I thought my cleaning routine of scrubbing with salt and wiping with oil was fine. I put some oil in the pan, turned the heat to medium high, turned around and started chopping some garlic. I heard a big pop and turned around to see the pan cracked and the oil just smoking a little.
After I looked it up online, my guess is different rates of thermal expansion caused the crack, the oil didn’t coat the entire interior of the pan and I just let it get too hot without anything in it. I also learned I could probably weld it shut and use the pan again, and while that sounds cool I don’t have the knowledge or tools to do that. Maybe another time.