Look at the bottom of the porcelain plate. If there's a hand-painted factory stamp with the Limoges, France, insignia, it's more than likely authentic Limoges porcelain. There should also be another printed stamp that says hand-painted (peint main). However, any porcelain plate with a stamped "C" or "RC" next to the insignia means it's an imitation, produced in the Republic of China.
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