I used to do a bit of firing at art school. Pretty sure later-tech made glazing as easy-peasy as possible, but IMO it’s pretty dang impressive what the Egyptians did, here: https://chatgpt.com/share/69ee869d-3784-83ea-951a-dab487fc6222 (eh, sorry for the source, but it’s one of the few areas where I feel like LLM’s combine to be useful x generally reliable)