Clams are usually thought of as fresh water. We did find pearls in some of the fresh water clams we dug up, even a blck one (much more rare).
Oyster are usually found in salt water or oceans and are much larger. These are where we get the much prized pearls you refer to.
The line you like is not so unlike the hidden man of the heart whom God is quietly molding and shaping into a vessel of honor as the K.J. scriptures refer to it. The wise men and women who still seek Him – so to speak.
Where eagles fly,