Not French, not British either.
Ste could stand for sterling fineness (925), maker`s initials RJ.
That's all I can tell. Unless the same mark emerges on silver positively identified, I doubt the mystery can be solved.
Thank you so much AG2012
for your response. Very interesting, after a little more research I believe the RJ and could possibly mean this is an RJ Graziano piece (US), it appears he has sold items via retailers who have then placed their own stamp on it, such as Avon. The Ste in this case is probably not for sterling as it is in the oval with other marks and will likely be the logo of the shop who retailed it. Many thanks, far too many days of head scratching!