Antique Victorian Rose Cut Diamond and Sterling Silver Brooch with 9KT Pin

This is a jeweler’s handmade brooch/pin from the late 1800s. It has 57 Rose Cut black diamonds, with seven larger of them forming a flower in the center. The ten open work petals surrounding the center diamonds each have five diamonds. The pull pin clasp on the back is 9 Kt. yellow gold. This piece is in very good condition. I don’t know the carat weight of the diamonds. Measures 1-3/4”w x 1-3/4”h Weight: 9.75 grams