These coins are made of low-grade silver (called billon) and come from the old German State of Montfort. The catalogs give the follow values for all dates except 1750 and 1751:
worn: $8 US dollars approximate catalog value
average circulated: $40
well preserved: $120
For some reason the Standard Catalog of World Coins lists 1750 and 1751 coins as more valuable. However, reviewing recent auction pricing these dates do not seem to carry such a premium.
The secondary picture to the right is requester Ad's coin. It is in poor condition. Approximately:
COIN AT UPPER LEFT: $100 coin
COIN AT RIGHT: $5 coin