Sterling, coin and fine silver
Almost all silver jewellery is sterling: 92.5% silver with copper making up the rest, stamped 925, STER, STG or STERLING — all four mean exactly the same thing. Older continental pieces are often 800, Scandinavian ones 830. Britannia silver is 958 and appears mainly on British work. Fine silver at 999 is bullion rather than jewellery, because it is too soft to wear.
The arithmetic is identical to gold: weight, times fineness, times the per-gram silver price. A 40 gram sterling bangle holds 37 grams of pure silver. What differs is the scale of the answer — silver trades at a small fraction of gold, so a piece that feels substantial in the hand may hold only a few pounds or dollars of metal.
The awkward truth about small silver
Silver is the one metal where the melt value of a typical piece is frequently less than the effort of selling it. A sterling ring weighing 3 grams contains under 3 grams of silver. At most spot prices that is a single-figure sum before the buyer takes a margin, and many buyers set a minimum weight below which they will not deal at all.
This cuts the other way for tableware and flatware, where the weights are large. A canteen of sterling cutlery can run to several kilograms, and there the metal value is real money. It is also where the melt-versus-resale question bites hardest: a complete, named, matched service is usually worth considerably more intact than melted.
Watch for plate. EPNS, "silver on copper", A1 and nickel silver all contain either a microscopic layer of silver or none whatsoever, and no refiner will buy them. Nickel silver in particular has no silver in it at all — the name describes the colour.