Two pictures are attached, of the brooch itself and the silver marks on the back.
The brooch is circular, approx 36mm or 1 7/16 in across with a design of six thistles radiating from the centre. A crown gem fitting in the middle holds a dark smoky cairngorm quartz stone, cut octogonally, flat on top and pointed to the bottom. Cairngorms are usually a brighter orange colour, so this may be another stone - I'm not sure what. The stone measures approx 16mm or 5/8 in across, and approx 10mm or 3/8 in high. It was my mother's and the silver had gone very dark - I've just cleaned it a little with a polishing cloth, though the design retains a lot of tarnish. There's a straight pin across the back of the brooch, with a flip security fastening.
I can identify the silvermarks for Edinburgh and Scotland, the castle and the thistle. There's also a date mark of P, but I have difficulty matching it to the examples on this website - can anyone help me there. There's also a maker's stamp - it looks like FS, with a bullet point between, and the F doesn't really seem to have a middle leg. Maybe PS? Very small and quite hard to make out. Hope the picture of the marks help - I did my best with a super macro zoom on my digital camera.
Many thanks in advance.
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