Things were very grim in Germany. War, human atrocities, ruthless dictators, crushing defeats, and financial collapse plagued the nation. German cities issued their own coinage since the imperial coins were completely worthless. It was an emergency and replacement money was needed. That's what notgeld means: emergency money.
This piece of notgeld from the Rhine-Ruhr region is particularly gruesome. The coin was struck at 33 mm in diameter, designed by the famous German medalist Karl Goetz. Greek god Prometheus appears on the obverse, chained to a rock with an eagle eating his liver as part of his eternal punishment by Zeus. On the reverse a child appears in an eternal flame. There are incused letter on edge: NOTGELD.
There are three denominations of the Rhine-Ruhr notgeld:
50 million mark -- brass
100 million mark -- white metal or silvered bronze
500 million mark -- gilded metal
As to value, these particular notgeld are particularly valuable. Approximate catalog values run like this for all three denominations:
worn: $10 US dollars approximate catalog value
average circulated: $25
well preserved: $60
Our general page on notgeld, with more pictures, values, and information, appears at this link [PRESS HERE].