I blame the wife !. The only markings on the brooch are TW 9CT. My wife confidently stated this meant total weight 9 carrats. In fairness she showed me one of her rings with diamonds (small ones) that was stamped that way. Also looking on the net seemed to back her theory up !. Further research though this morning as proved that the stone is in fact a citrine, and the brooch Victorian, I found it though at the site of Georgian hunting lodge. As I said there's no date stamp, or city on the brooch. The gold looks better than 9 carrat, and the citrine is a wonderful yellow. As for value, hundreds rather than thousands. I wont sell, I will have a safety chain fitted to it , the wife's claimed it any way. Still a great find, and one to keep in the family. Must dash, off to search a local wood, it's full of coins many pre-decimal, so my scrap silver collection should get bigger, I will weigh it in just before Christmas.
Keep Digging
Robert.