Dear Bill;-
    Your friend is absolutely right. Shells, which are calcarious cytoplasm,
are created from the  (mostly) large seaweed fronds. The fronds break off, and
on their way to the bottom of the sea, curl to the right in the Nothern
Hemisphere and to the left (or sinistralia) in the Southern Hemisphere. The
individual protoblasts are replaced by calcium carbonate molecules which
inhabit all salt waters. On reaching the bottom, the new shell-like creatures
are subjected to tides and tsunamis which wash them ashore in places such as
Florida and New Jersey.
    The Answer Man

"William Bednarzyk, Jr" wrote:

> Hi there,
>     I signed up with this group for one purpose.  A friend of mine tells me
> that seashells are made from seaweed.  I tried telling her that seashells
> are the creation of mollusks.  She really believes this, so I thought I
> would post to this group to see if I can get an answer I can use to explain
> this to her.
>
> TIA,
>
> Bill Bednarzyk, Jr