I also bought the purple sand electric stewing cup of Xiaoxiong, and later asked the person who runs Xiaoxiong, and she said that this is actually just ceramic pot, so it won't matter. You can go to see it now. The same model is still selling well, but all the products sold have been renamed as ceramic electric stews.
I asked if purple sand was changed to ceramics after something went wrong, and she said that it had always been ceramic pot.
So what we are facing is probably that they sold ceramic pot as a purple casserole at the beginning, but it was a mistake.