lm, Not sure if you are talking about ‘black coral’ or not. If you
are, the rind would be the remains of the actual coral animal! Black
coral is, after all, nothing but a protein skeleton of the octocoral
animal. If the coral was torn off a reef and bumped around awhile in
the surf, the coral crust (or rind as you say) is knocked off and only
the black (brown when wet) skeleton washes up onto the beach.
Sometimes it is ripped off the reef and is carried directly onto the
beach with the crust still intact. I work with a looottt of coral and
find the easiest way to get the crust off is…let the coral dry and
then either roll the crust in your fingers till it crumbles, or bang
it with a piece of wood and it will crumble off. Sometimes the crust
is different colors…bright red, yellow, brown, gray, white, etc.
Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry!