That's FAR too broad a question to answer accurately. Germany issued dozens of different denominations of coins with hundreds of designs.
Please post a new, separate question with the coin's date and denomination. For most common coins the denomination will be given in pfennige or marks.
The value of a 1929 10 German pfennig coin can vary depending on its condition, but it is typically worth around $1 to $5 USD in the numismatic market.
Cash Value : about half a Euro. A one-mark German coin has a value based on the old exchange rate with the Euro. In 2002, the old Deutschemarks were invalidated as legal tender, but marks were exchangeable at the rate of 1.95583 Marks per Euro, which was set in 1999. So the coin may have more or less value as a collectible than if redeemed for Euros.
The value of a 1920 German coin can vary depending on its condition, rarity, and precious metal content. It is recommended to consult with a coin dealer or a numismatist to get an accurate appraisal of its worth.
It's worth about 12 US dollars. For an old coin they are fairly common.
what is the value of the German mark coin with horse on back dated 1923
It's quite sacre, but all depends on the condition of the coin.
Please post a new, separate question with the coin's date. Without that information it's not possible to estimate a value.
50 centimes
The value of a 1924 German penny varies greatly depending upon the condition of the coin and where the coin was made. The values vary between $6.75-$81.00.
I think this coin is over 115 years old ,Its value can reach USD 2000,00
You need to know its denomination and mint mark. The best site I know for German coin values is www.sammler.com; however, most of it is in German. If you don't read German, please post a new question here and we'll try to ID your coin.
There's no such coin. Germany did not take the name Bundesrepublik Deutschland (German Federal Republic) until 1950.