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A general treatment of methods and a selection of references to preparation
techniques for microfossils (also works for larger fossils) is given in the
appendix of the book I edited "Fossil prokaryotes and protists" (Blackwell
Sci. Pub).  The key sentence there is "that every situation is unique and
the methods may require modification".  Experimentation really helps even
for rocks close together in the same sequence.

Quaternary O is a surface-active agent, and it is no longer available.
Substitute, safe agents include a number of other non-foaming agents, such
as Calgon.  Some of these mechanic's hand soaps that are put on and wiped
off will work.  Boiling is almost always necessary, thus you cannot use
foaming soaps, unless you or the custodian don't mind foam all over the
room.  However, if you didn't boil and just soaked and heated to
near-boiling, there are a good many strong liquid soaps available in
grocery stores and hardware stores that would do the job.  All of these are
most efficient if the sample is completely dried in an oven overnight so
that the surface agent can penetrate between particles (won't happen with
water in those spaces).

Whitey Hagadorn (who is at USC and commented) could ask his Dean, Bob
Douglas, about how we used to do it at UCLA when we were all grad students
together.  We couldn't use the technique now because of safety and
environmental regs, but we dried the samples overnight, soaked them in
kerosene overnight, poured off the kerosene, and boiled in water with a
handful of bicarb of soda.  Then we sieved and if big pieces were left, we
just repeated that process until the sample broke down completely.  We did
some really gross stuff (especially Bob's K samples from the Great Valley
Sequence).  The only ones that would not break down eventually were those
cemented by CaCO3 or SiO2.  Another real hazard, as Bob and I discovered on
several occasions, was that the kerosene seeped out of the interstices
during boiling, floated to the top of the pot, then over the edge, and
ignited.  Not good to come into the lab and see a whole bank of burners and
pots in flame!

Here at Berkeley years ago, Kleinpell used to put a small, heavy roller
with sharp points all over it and rubber rings over the ends to role on
inside a jar with sample and water (maybe some other stuff too, but we
never used the technique).  He then rolled the samples on a roller mill for
hours until the sample was pulverized.  Worked too.  The sample and
microfossils were all broken up.  But for gross work (i.e., ids only; but
certainly not illustrations), a sample could be processed fast and you
could get your stratigraphy done  quickly.  Wouldn't want to keep the
microfossils in most cases, though.  I found a whole drawer of the rollers
when I came here--they make fantastic paperweights.


Jere H. Lipps
Department of Integrative Biology &
Museum of Paleontology
University of California at Berkeley
Berkeley, CA 94720
510-642-9006 fax 642-1822
jlipps@ucmp1.berkeley.edu