David:

Normally sighted people usually do not pick up many micro shells by
seeing them and putting them in a goody bag except for the longer end of
the genre.

The most effective way is to bring along several plastic bags and pickup
rubble or algae and shake them into the bag. Usually along with small
bits of rubble and micro shells.  Alternately, bring the material to the
surface and carefully remove the micros.  I also used to look for sand
that appeared to be good and put a handful into a bag for later sorting.

When looking for other shells in sand if they were small, I would put
them into a plastic jar with a flexible cover with a slit in it.
--
Aloha from Wesley M. Thorsson, Editor of Internet Hawaiian Shell News
     122 Waialeale St, Honolulu, HI  96825-2020,  U.S.A
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