The height of the shell attains 3 mm, its diameter9 mm. The shell is patella-shaped, ovate-oblong and symmetrical. The apex is subcentral. The shell is radiately ribbed. The ribs are strong, convex, simple, whitish. The interstices are irregularly marbled with brown. The interior is vividly pearly, with a rather large central spot of dullwhite notched in front, and bounded by the whitish muscle-impression. The rest of the inside has a nacre of unequaled brilliancy with opalescent reflections.