I am not quite so cynical. I believe we collect and wear jewelry for a far baser emotion. Have you ever walked on a beach and picked up an object of interest? I have, and I have often been pleased with the result. You see I believe we collect that which appears to be of interest to us. Perhaps we find it beautiful or maybe its just the novelty of the item. Often we keep these objects and add them as part of our treasure.
That would seem to imply the first jewelry would have been objects of interest found in the local environment. The excavation of early funeral sites seems to support this opinion. People collected shells, bone fragments, feathers and teeth.These objects were strung on a cord and worn as jewelry.
As homo sapiens learned to create tools and work metals our jewelry collections became more sophisticated. The jewelry wearer was born!
If people have been collecting objects of art (jewelry) for over 25,000 years why havent we found more jewelry than we have? To answer that question lets look briefly at the Egyptian dynasties that encompass some 3000 years. Clearly the Egyptians highly valued gold and gemstones. They excelled at prospecting, mining and manufacturing jewelry. As rich as many of these dynasties were they were limited by the extent of known mineral resources. Demand was high. Supply was limited. Throughout the ages tombs of Pharaohs were pilfered for the treasures they held. It is likely this plunder was melted down and reused.
Today jewelry damaged or out of style is recycled. Sometimes the pieces are reworked into more contemporary designs. Sometimes the metal is sold as scrap. Whatever the outcome the precious metals and gemstones are saved for later use.