A collection of four rings

A collection of four rings, comprising: an amethyst ring, mounted in gold, size O1/2; a sapphire and diamond seven-stone half-hoop ring, mounted in gold, size S; an asymmetrical ring in white gold knife wire, set with quatrefoils of brilliant-cut diamonds, size R, stamped 9KT; and a pearl and diamond cluster ring, mounted in gold, size J1/2, pearl untested