definition
in relief: 1 Art carved, molded, or stamped so as to stand out from the surface.
Found solid black due to tarnish. No indication for type of base metal.
Leonardo DaVinci’s “Last Supper” cast in copper, 10″X5.25″ with stand for table (not for wall mounting). From: Charles Frazee estate.
noun: 1 a feeling of reassurance and relaxation following release from anxiety or distress:
Check out How to Clean Copper method No. 6
Ketchup
elfcroft 
What a great piece of art for you all to find. I like it. I had herd you could clean copwr with what you used. Now I know. Great job,
Ou