I have my grandmother's white akoya pearls that she bought in the 1950s or 1960s, and she tended to buy the least expensive gems instead of good quality. They had rather thin nacre. She wore her pearls daily, and when I inherited them in 1980, I wore them constantly until last year. Once I discovered Pearl Paradise, I ordered some pearls to replace them, because after 60-70 years, my grandmother's pearls were looking a bit dull and a bit flakey in places so I could see the shell bead inside the pearl. I still could wear them, but my new pearls are so much nicer.
Necklaces will wear out faster than earrings, just because necklaces will be rubbing on your neck and collars, and earrings won't be rubbing against anything. However, good pearls should last decades, so wear them and enjoy them daily.