This is a very pretty mother of pearl shell brooch, which is very dainty and would have probably been worn on a jabot at the neck, it has a simple pin fastening and measures 1.1/4 inches x 1 inch (3.2 cms x 2.5 cms).
This is an exquisite very large oval brooch set in etched silver tone metal with a barrel clasp. This could be used in many ways but originally I think it would have been used on a belt set on a dropped waist dress fashionable in the 1920s. Measurements are 3 inches by 2.3/4 inches (7.6 cms x 6.8 cms).
This is a very unusual moth brooch (at least I think its a moth) set in silver with the head shown as an amethyst and the body in abalone. The wings and tail are etched. Measurements are 2 inches by 1.1/4 inches (5 cms x 3.5 cms).