Need make and model. You cannot identify year of manufacture even with the make and model on most firearms.
Has nothing to do with firearms.
Blue Book of Gun Values
Unable to answer without a LOT more information- if then. Many low dollar Belgian firearms have very few records.
The Complete Catalogue of Firearms or The Gun Trader's Guide are two good references. You can also send me a message using the message board here with all information on your revolver, and I can check my references. However, some guns have little public information available.
Insufficient information to answer the question. Identify the item in question and resubmit.
Ruger's website lists the current offerings.
There are examples of "revolving barrel" firearms made before 1500 AD.