I have doubts about enamels. For middle 18th century orange should not be opaque-shaded enamel of tangerine tone, but should be iron-red. Yellow should be transparent and quite shiny/brilliant.
doucai cup by: peter
This is a doucai cup. I do not have enough experience to judge authenticity of doucai items. They were already rare and costly centuries ago. Either it is new or very fine. Again, I have doubts about the foot rim as it shows no clear age signs. Please ask for a second opinion.