What kind of revolver has a crown over a R?

Answer 1

One that was made in Belgium. What you see is a proof mark. In many European countries, firearms must be submitted to the government proof house for testing (being "proven" safe to shoot). The crown above the letter R was a mark of the Proof House of Liege, Belgium that went into use in 1852 for handguns. Beyond that, it does not tell us anything about WHO made it, or what it is. Sort of like the Underwriter's Lab sticker on an electrical appliance. Sticker does not tell me what the appliance is, just that it is safe to use.