Very Small 1923 A Rentpfennig Coin/Token? | Play Money

I suspect it is a play money. I was in a similar predicament a while ago.

... and here's what I pulled off Wikipedia (ya learn something every day!):

"The Rentenmark replaced the German Deutsche Mark. Due to the economic crises in Germany after the Great War, there was no gold available to back the currency. Therefore the Rentenbank, which issued the Rentenmark, mortgaged land and industrial goods worth 3.2 billion Rentenmark to back the new currency. The Rentenmark was introduced at a rate 1 Rentenmark = 1012 Deutsche Mark, establishing an exchange rate of 1 United States dollar = 4.2 RM.

The Rentenmark was only a temporary currency and was not legal tender. It was, however, accepted by the population and effectively stopped the inflation. The Reichsmark became the new legal tender on 30 August 1924, equal in value to the Rentenmark.

The monetary policy spearheaded by Hjalmar Schacht--the Central Banker--together with the fiscal policy of German Chancellor Gustav Stresemann and Finance Minister Hans Luther brought the inflation in Germany to an end.

The Rentenbank continued to exist after 1924 and the notes and coins continued to circulate. The last Rentenmark notes were valid until 1948.
[edit]Coins

Coins were issued dated 1923, 1924 and 1925 in denominations of 1, 2, 5, 10 and 50 Rentenpfennig. Only small numbers of Rentenpfennig coins were produced in 1925. A few 1 Rentenpfennig coins were struck dated 1929. The 1 and 2 Rentenpfennig were minted in bronze, with the remaining coins in aluminium-bronze." - from Wikipedia

And yes, you and svslav are correct - it's a piece of play money.