Standard tweezers are not suitable for microshells, for the reasons David
stated. But biological supply houses sell very fine-tipped tweezers (they
call them forceps), with which you can actually pick up an individual grain
of sand. These are invaluable not just for general handling of micros, but
also for such tedious jobs as setting opercs in extremely small shells
(under the microscope, of course). Microshells can also be easily picked up
using a small, fine-tipped paint brush (as found in childrens water color
sets) dipped in water. Dip the brush, remove excess water by touching the
brush to a paper napkin. Then, when you touch the brush to a microshell, the
remaining moisture will cause the shell to adhere, and it can easily be
transferred to another container, or wherever you want to place it, without
damaging it.

Paul M.