That horseman looks like he means business, Barbleman!
These old coins were issued by Holland, part of the Kingdom of the Netherlands, in the mid to late 1700s. Virtually the same pattern and inscriptions were used on several different coins in several different denominations, and some date back to the mid-1600s. Find yours in this list:
7 gulden: gold, 21 mm diameter
14 gulden: gold, 26 mm diameter
1/2 ducaton: silver: 26 mm diameter
1 ducaton (silver rider): silver, 42 mm diamter
If genuine, and if in good shape like the coin in our picture, all these coins are valuable. Worn, dark, or damaged coins will be worth far less.
NEVER CLEAN A COIN. CLEANING RUINS VALUE.
Here are very approximate catalog values for coins in average circulated condition. The specific data of these coins does not matter very much. What makes a coin more valuable is the condition it is in. The coin in our picture is better than average circulated, so it would be worth about 1.5 times the values below. Worn coins would be worth half these values. Damaged coins (with cleanings, scratches, stains, nicks, gouges, etc.) would be worth far less.
7 gulden: catalog value $350 in average circulated
14 gulden: $450
1/2 ducaton before 1760: $250
1/2 ducaton after 1760: $150
1 ducaton before 1700: $450
1 ducaton after 1700 and before 1760: $300
1 ducaton after 1760: $200
These are catalog values. Use our Important Terminology page to understand what this means. If you have a nice-looking specimen of any CRESCUNT CONCORDIA coin, seek out a knowledgeable collector or professional coin dealer for an in-person appraisal.