The famous flow-blue china was made in England and in the Netherlands from about 1830 to 1900. The designs were printed on the plates and the cobalt coloring that was added flowed from the design to the plate. The smeared effect was colorful, and hid most of the defects in the pottery. Almost all the flow blue was printed on ironstone china. Ironstone was cheaper than porcelain, and did not chip, stain, or craze easily.
Historical china is often of the flow-blue or "bleeding-blue" type. Collectors differ in their judgements of the best type of flow blue other than those of historical designs. Some like the very dark, heavily smeared blue pieces (like the one shown above), while others prefer the lighter blue with more legible designs. 
