JR will be the maker's mark - usually, but not always, his/her initials; the anchor is the assay mark for Birmingham, where the silver's purity has been tested; the lion is the quality mark which shows the metal is Sterling silver assayed in England; and the C is the date mark. If you want to find out the year the piece was assayed (and probably, though not necessarily, also made) you'll need to Google for Silver Hallmarks; the date letters go in alphabetical order, but the typeface changes each time the alphabet is exhausted, and since hallmarks have been around since the 14th century they've gone through a lot of alphabets! Best of luck!