They are very delicate, maybe bone China
I do not know, they have been in my family
Chinese bowls with Dragon decoration made second half 20th century ( after 1970 ). Mark tells about Precious product bowl. Bowl is tranferprinted, so not hand painted and are made for export to western country's. Indeed they are ricebowls and meant to keep the rice warm for longer time. I would not expect a lot of demand for this recent bowls. Collectors are looking for older bowls and handpainted ones.