19th century opaque fine earthenware plate from Sarreguemines

Rare, superb polychrome plate with a floral bowl from the 19th century, in opaque earthenware from the Sarreguemines factory, diameter 21.7cm. On the back, a coat of arms of Lorraine surmounted by a black crown (circa 1857-1914) and the number 5a engraved. Opaque is a fine white earthenware obtained by adding kaolin to the paste at a rate of 25%. It is also called: half-porcelain, opaque porcelain or ironstone. This plate is over 100 years old, which explains the missing enamel (see photos). The reverse is well preserved.