James Kent, original, not a copy. Many colourways were not recorded, that applies for many potteries. Variations of their backstamp include...
That would be my guess as well
You can find links to registered design number sites on the web. Here is one. The diamond mark version 1 was used 1842-67 The diamond mark...
But the spellbinding, splendiferous, totally wonderful result of all this ignorant flummery is........ ..........you get the chance to buy some...
Separate names with a comma.
