Zellij

A zellij panel is assembled from tesserae cut one at a time with a hammer, by a maâlem who holds the pattern in his head. There is no drawing to work from. The geometry is six hundred years old and still cut by hand in Fez, which is why it belongs in a collection about masters rather than one about pictures.

This comes from a craft people still practise. It is nobody's private property and it is not nobody's work either: it was made, over centuries, mostly by women whose names were never written down. We say so rather than call it anonymous.