Curaçao is an island in the southern Caribbean Sea, north of the Venezuelan coast, that is a constituent country of the Kingdom of the Netherlands. These nice silver coins were minted in 1944:
1 GULDEN: 0.232 troy ounces silver
2 1/2 GULDEN: 0.579 ounces silver
Values of these coins are a combination of their silver value, called 'base value' or 'bullion value' (BV), and their collector value.
First, compute BV by multiplying the current price of silver by your coin's silver content. For instance, if silver is selling at $15 US dollars per troy ounce (look it up, it changes every day), then BV for a 2 1/2 gulden is 0.579 x 15 = $8.70 US dollars.
Second, add collector value depending on condition:
worn: BV + $1 US dollar approximate catalog value
average circulated: BV + $10
well preserved: BV + $25
fully uncirculated: BV + $50
2 1/2 GULDEN
average circulated: BV + $5
well preserved: BV + $8
fully uncirculated: BV + $12
Coins that are damaged, cleaned, scratched, stained, or mutilated are worth only BV.