A topaz and diamond cluster ring

A topaz and diamond cluster ring, the oval mixed-cut orange topaz measuring approximately 18.8 x 12.75 x 7.4mm and estimated to weigh 13.1 carats cut down set in gold collet, surrounded by old cut diamonds estimated to weigh 0.95 carats in total, cut down set in silver to gold mount with split shoulders, gross weight 10.6 grams. Circa 1860

No. 28465M