I am no expert in 19th Century Polish coins. But, I am always fascinated by Central European history. Poland seemed heavily dominated by other nations. Depending upon which year you were speaking of, territory might have been Poland or Prussia/Germany or Austria-Hungary or Russia.
I believe Austria-Hungary used a gulden in Galizia which was Poland, but now is Western Ukraine.
Take a look at pp.30-31 in this text. It speaks of silver and gold gulden coins used by Austria-Hungary, in addition to 4- and 8-gulden gold coins. It describes a drop in the value of silver at the time.
The following gives you additional color for 18th Century Polish coinage, which while not directly germain to your question will help you see Prussia's role in manufacturing Polish currency.
When you speak of value, you need to decide what specifically you want.
- The value of a gulden in 1896, adjusted to 2009
- The value of a (I'll assume silver) gulden coin from 1896, melted down in 2009 terms
- The collector's value of a (silver) gulden coin from 1896, in 2009 prices
This is not a job for your average coin collector. I would suggest getting 2 or 3 estimates from experts who specialize in coins from this period and region.
You have national boundaries that are shifting over time. You have different monetary systems that are being integrated over time. You have differing inflation rates. You have rare metals such as silver and gold that have been fluctuating in value over the years. And, today, you have national currencies that float. So, you almost need a sophisticated econometric model to answer your question... :)
If your Q is serious and you possess such a coin, I suggest contacting 2 or 3 coin dealers that specialize in this time period for Central European coins.