This is a lovely Victorian (circa 1870) Scottish brooch. It is fashioned of silver (sterling, unmarked but tested) and agate that I was once told, by a Scottish dealer, was called Montrose. She further told me that it was all mined out now. The interesting thing, though, about this brooch, is that it's the only horseshoe brooch I've seen which features a nail, again out of silver and Montrose. The brooch is in excellent condition, with it's original "c" clasp and "t" hinge, and all the agate pieces are present. The brooch measures 1 inch and 3/8 North to South, and an 1 inch and 1/4 East to West. It weighs 7.51 grams.