willow pattern meat platter

[molly]

I have an old (probably 19th century) willow pattern oval platter. Does anyone know how to date it and what makes a good or bad one? There are no marks underneath other than a tiny '14' impressed into the clay. It is completely flat underneath, no ridges. I inheritated from my grandmother and would love to work out how many generations back it belongs.

[firefly]

Willow pattern is of course an English design based on a Chinese story where some lovers escaping an island by becoming birds. In my untutored eye most of them would look the same, though I imagine platters would be rarer than dishes or bowls.