"Here is another one- terra sigillata. It is a slip (fine clay particles in suspension) used to decorate and seal ceramic ware. Probably one of the earliest glazes. "

And what language is that, "terra sigillata"? I've spent a lot of time talking about terra cotta, and terra what ain't cotta yet, and picking terra out of my teeth, washing it out of my clothes, and brushing it out of my hair. I have a pottery studio, and have often wondered how to pronounce the g in "sigillata". Different potters follow different faiths on that one. I sidestep responsibility by never saying it in polite company. Which, that's easy, since I'm almost never in it.

It's also interesting to me that the term "terra cotta" has a connotation of being brown, or reddish brown. Obviously not all pottery uses brown clay, or there wouldn't be "terra alba" for pipe clay. I wonder what the white earth is they're using for pipe clay. Porcelain? Kaolin? Are pipes usually white?