A collection of jewellery, late 19th/early 20th century, comprising: a ruby and diamond cluster

A collection of jewellery, late 19th/early 20th century, comprising: a ruby and diamond cluster ring, size N, stamped 18ct Pal; a five-stone diamond ring, size N1/2, stamped 18C; a bar brooch of knife edge design set with five circular-cut diamonds, length 5.3cm; and a gold ring rubover-set with a cushion-shaped diamond weighing approximately 0.50-0.60 carats, size M