This is an exceptionally rare Antique French Porcelain Plate believed to be by Limoges dating to c1880.
It is decorated to the front with a colour chart each colour named in french. The centre is entitled 'Couleurs Vitrifiables De A. Lacroix Chimiste A Paris'.
Alphonse Lacroix was a French Chemist based in Paris who's research centred around the decorating methods of porcelain and glass.
This plate is numbered 56 so I believe was part of series of colour wheels.
