French Art Deco stylized swirl “Seashell” clip / brooches with the maker’s mark of Pierre Maillard in 18k gold set with 82 round-cut diamonds (approximately 4 carats TW)

French Art Deco stylized swirl “Seashell” clip / brooches with the maker’s mark of Pierre Maillard in 18k gold set with 82 round-cut diamonds (approximately 4 carats TW), marked: P and M (maker’s mark of Pierre Maillard, rue St. Martin, 75003, Paris) in a diamond poincon, (2x), French Eagle’s head assay mark for 18k gold (4x), c. 1938