You are definitely not asking for too much, and I would
suggest that you also require return of any samples
made to run the tests, in case future researchers
want to re-examine them.  Many labs will state that
they retain all samples processed, but given the often
limited lifespan of testing laboratories or facilities, it
would be best to keep the samples together with the
collection, as documentation of the specimen and
actions taken on it.  If the procedure is destructive (in
that no sample remains after the test), then ask for
copies of all raw data, so that these too can be
reviewed by other researchers.  Have the lab state
specifically the procedures (chemicals, instruments,
software, etc.) used in preparing and running the
sample, and how the results were interpreted.
 
You may also want to ask for personal references for
the researcher and the laboratory.
 
Good luck!
 
Suzanne Griset
U.S. Army Corps, St. Louis District, PD-C
Archaeological Curation and Collections Management
Branch
1222 Spruce St.
St. Louis, MO 63103
(314-331-8865)
[log in to unmask]