These nifty boxes were made by collecting porcupine quills which drop naturally from the animal in the late 19th/early 20th century in Ceylon (now Sri Lanka) which was an important trading post in the Indian Ocean. Ships traveling from the West to the East would take supplies there. These boxes were produced as souvenirs for sailors. Many of these boxes can be found with ivory dots, ebony or bone inlay and with an elephant on the inside. I once read that the closer proximity of the ivory dots together, the more valuable the box.
Being a versatile little box, you can keep anything in them, maybe save special cards, letters, postcards photos, or use as a writing box. These boxes can be difficult to find, since many are antique and are valuable. 1stdibs is a great resource since it links so many antique stores to a central location.
The March 2011 issue of Veranda mentioned the porcupine quill box as actress, Julianne Moore's "Favorite Thing"
Veranda March 2011
Notice the various shaped and sized quill boxes on the coffee table by Phoebe Howard
An exceptional box, notice how the dots are very close together-Antiques Council
1st Dibs-Benjamin Wilson Antiques
1st Dibs-Ad Lib Antiques
Here is a small hexagonal box that shows the elephant on the inside with Ceylon where it was made with a somewhat souvenir appearance.