This species lives buried just beneath the surface of sandy seabeds, where it feeds by filtering tiny food particles from the surrounding seawater. It is found in coastal and offshore waters, generally in areas with moderate water movement.
Brooch shells are often described as living fossils, belonging to an ancient group of molluscs that were once widespread throughout the world's oceans but are now represented by only a few living species, all found in Australia.
Although N. margaritacea is widespread in Tasmanian waters, its shells are not commonly found washed up on beaches.
