Beautiful Portrait of One Stylish Young Lady on Porcelain Plaque

When I purchased this portrait she was trapped in a very ill fitting shop bought frame. I have had it professionally reframed in a 'Hogarth Style' frame so it can be immediately hung and admired while waiting if preferred for that perfect contemporary (to the plaque) frame to come along. The portrait is painted on a porcelain plaque and is neither signed nor dated but I think it is extremely finely executed. It is difficult to date these plaques as the glazing process helps to retain the strength of the colours but my instinct is this one would date to circa 1820, from both the dear lady's possibly crinoline dress and those impressive ringlets. I have unsuccessfully tried to find if this portrait was a copy from an original painting but have to failed to do so, so it is just possible that this unusually was a portrait of a living individual, not the romantic female subjects one often sees. And I am so grateful for that.