Need Help for identification! - dragon dish

[Max Kep]

Thank you so much. Thanks to your help I could figure out
what kind of ware it is and its date, I fund the same plate at the auction.

(Porcelain cut ?Blue of Hu??, China for Vietnam, Hu?, the XIXth century.
Coupe en porcelaine d?cor?e en bleu sous couverte d?un dragon volant
parmi les nuages sur fond bleu. Au revers, la marque ?Ngoc? (tr?sor).
Diam. 14 cm.. 

As far as I understood hieroglyph which means the mark on this plate is only one, which means the brand.
And can you please tell me what is written on my plate? Which one of these kinds is Ngoc?

[peterp]

The character on this plate is ? which means simply 'jade'. There are no brands in Chinese porcelain.