Matinee necklaces are great for layering jewelry because they are longer than princess length and shorter than opera length. These necklaces fall somewhere between the collarbone and the center of the bust. Beads string multi-colored necklace. The size of necklace sid usually 20-22inch. Since the necklace is so low, a variety of necklines are appropriate. Consider layering a long opera long necklace with a choker necklace and a V necklace to add some contrast.