This lovely antique pin is noted as Victorian by seller Jack Weir, but I think it might be later. If you look at the reverse photo, the pin stem doesn’t extend beyond the clasp, which was a typical Victorian feature. It’s possible the stem was replaced at some point, or maybe it really is of that period.
The piece features open backed diamonds and spinels, with a centre piece of a star sapphire, set in silver and gold. It sells for USD$5,750.