Thankyou all for your help. I have some great leads to follow there, much appreciated. I am now convinced that it is a Stuart Crystal goblet, the stem is exactly like the one on ebay, thankyou for that!
I have never been to a jousting tournament, do they have souvenirs such as this for sale at these tournaments?
The Masonic link is interesting also, something to follow up.
I wondered if it could possibly be an award or trophy specially etched for a sporting event or competition....
Many thanks again, I'm off googling!
Janet.