Necklace lengths, in our current era, have more to do with personal preference than fashion requirements. Few will be mortified if you wear Opera-length baubles in the afternoon, in fact, many only notice the names for necklace lengths when purchasing a traditional strand of pearls.
When creating jewelry designs, the ability to adjust standard sizes is an artistic freedom and a service to you. Traditional names of Princess, Opera, and Matinee refer to a Lady's beads. When designing for gentleman, forego the names and consider the drape. Whereas one might enjoy handling a full rope or lariat, a great many men (and women) seek a size that lies upon the chest at a manageable span with which they need not fuss. General measurements are listed below with traditional names for assistance in communication.
13" to 16" Collar & Choker lengths should be comfortably close fitting, lying above the collar bone, or up on the neck.
17" to 19" The Princess length is probably the most common necklace seen in the graduated strand, although any style necklace can be made in this standard length, which rests beautifully just over the collar bone.
20" to 24" The Matinee is a lovely drape of beads most definitely on the chest, a length still sufficiently sportive to be worn for daytime activities, as opposed to the...
28" to 32"Opera length strand, which may
Over 45" The Lariat or Rope is a long string of beads, which can be looped, wrapped or draped, as one is inspired. What is the difference? Rope may or may not have a clasp; a Lariat is an extraordinary length without a clasp.
The Graduated Strand
Multiple Strand Necklaces