Three gem-set gold novelty brooches, the first designed as two rose-cut diamond-set ostriches

Three gem-set gold novelty brooches, the first designed as two rose-cut diamond-set ostriches applied to a bar, 4.5cm wide, fitted case, the second modelled as a leaping frog, set with cabochon emeralds in gold (one deficient), diamond-set eyes and front claws, French control marks, 4.7cm, the third modelled as a bird with green eye and ruby-set collar clinging to a reed, French control mark, 4.9cm