Nowadays, ceramic wine jars and jars are all commercialized. They use machine molds and coal and natural gas to burn a lot. I don’t know whether they are poisonous or not, but the quality of the wine can’t be compared to traditional handmade ones. Old-fashioned dragon kiln, fired with pine wood. It is recommended to take a look at: Guangxi Lingshan Ceramic Wine Tank to see if it is suitable for you and may be helpful to you.