Hallmarked in Newcastle-upon-Tyne

I don't live very far from Newcastle but this is the only piece of Newcastle silver I have. It is a large serving spoon. Hallmarking was discontinued in Newcastle in 1883 or 1884. I think this is from about 1813-15. Anyway I love it and use it all the time. 
The Hallmark is the 3 castles indicating Newcastle. The letter gives the date- after more research maybe 1815.  The lion says its silver. The monarchs head says duty has been paid and the letters IR and IW are the silversmiths-  John Robertson II and John Walton. So I assume the I stood for a J.
It gives me a thrill to think the spoon is over 200 years old. I wonder how many people have used it in that time.
The monarch in 1815 was George III but the country was ruled by his son by then as he suffered from mental illness- he has been called mad king George. His son became George IV when he died.