In his book, "Mercanti di Mare" Marcello Saija writes about the Cincotta family, among others, I assume, who were involved in coral harvest in the waters around the islands. Here is a photo of a photo...(I will try to scan it, but I am afraid that the quality will never be great) it is a Sterioptican photo from the 19th century. I could not buy the original unfortunately.
It is a picture of Trapani in Sicily of local people cutting polishing and converting coral into jewelry. Much of it was actually made into jewelry in Torre del Greco in the bay of Naples, not too far from Pompeii. I will post a few photos of 19th century coral jewelry that I own made in the area. The pieces, for the most part, that I own are not of extremely high quality, but they are at least interesting and representative of what was sometimes made.
Most of what is available are made from these rough branches of coral. Those that were commonly worn by the islanders tended to be more carefully cut pieces made into pear and bead shaped gems, set often in gold, but sometimes in gold fill(gold fill is a layer of gold forged onto the surface of a base metal.). The piece below...is a rather aristocratic piece and is set in gold; but that above and the stick pin two below are in gold fill. Notice the dark spots from oxidation of the base metal. These look much better in person. For some reason, the photos seem to accentuate the oxidation.
While you are looking at the lady in the cameo above, this may be the time to mention that in the second act of "La Boheme", Mimi moons over the "Corals" in a shop window as she and Rodolfo approach the hat shop to buy her bonnet.
These are from the Tyrhennian sea, below perhaps from farther east as they are quite ancient, but are representative of a type none the less. All are from my collection.