I'd like to practice my writing with brush, and came across this textile that I think is used a lot in schools at least in Taiwan:
It's called 水寫布 (water-writing paper). When wet it becomes black, so that writing in water is highly visible. After drying it returns to white color again. Great, but my thought is that there must be some tradtitional forerunner material to this – something simple that has been used in the same way? Like some chalk paint on black background or something? It seems like a too good an idea to not be older than this material :)
Are there some traditional or readily available materials that can work in a similar way?