pearl diver:
(also rarely ‘pearl fisher‘; plural: ‘pearl divers‘; for the right pronunciation, please click here)

a pearl diver at work
a person who dives into lakes, seas or oceans in search of pearls which can be sold,
e.g.
Though natural pearls are very expensive, the pearl divers are very poor because the traders pay them very little.
Unlike the pearl divers of the past, the modern day pearl divers use devices that help them to dive deeper and stay in water much longer so that they can find more number of best oysters in one dive.

a pearl formed in a oyster
