Metal rectangular plate Japanese pattern embossed

Metal rectangular plate roughly 24cm long, with a Japanese traditional scene.  The metal looks like copper, though the front is a lead grey colour.  The pattern has been embossed onto the metal in some way.  On the back there is a leaf pattern with small metal feet to make it stable on a flat surface.  It belonged to my great aunt and she died around 15 years ago.  I don't know how long she had it before that.