1
animal
bivalve
black
bright
calcareous
calcium
case
chitin
clam
close
coating
concave
conic
creamy
ebon
empty
exeskeleton
gastropod
glass
glossy
hard
hollow
isolated
ivory
layer
light
marine
mollusc
molluscan
mollusk
molusc
mussel
nacrous
object
ocean
ocher
one
outer
pearl
protective
sea
seashell
shell
shelter
single
snail
spiral
whelk
whole