Maybe you mean "too thick" instead of "too long"?  I use the same product,
but cut in pieces with the dimensions of a standard microscope slide
because we often want to have large viewable areas.  I've had no real
problems with them.  It should be noted here that, unless you are willing
to pay a TON of money for coverslips, no manufacturer will guarantee a
coverslip to be exactly X mm thick.  They will provide a range and it would
be incumbent upon the investigator to sort out the pieces that are too
thick/thin for a particular application.  As was pointed out in another
posting, there are very good reasons for using coverslips that are not
1-1/2.
Rob Palmer
CEB/UT

>Dear List Subscrbers,
>We were recently informed by a Zeiss rep that there may be problems with the
>larger glass coverslips.  We have been using Corning No. 1, 24x50mm
>coverslips but were told that they are too long!  Any comments, suggestions
>and clear explanations will be greatly appreciated.
>Sincerely,
>Jody Myers
>
>____________________________________________________________________________
>****************************************************************************
>
>
> Jody M Myers                             _ _ _ _ _ _ _ _ _ __ _ _
>   Department of Biological Sciences        FSU NEUROSCIENCE      -
>     Neuroscience Program                  - - - -_--_ _- -_     -
>       215 Biomedical Research Facility             -       -     -
>         Florida State University                           -     -
>           Tallahassee, FL 32306-4075                       -     -
>             904-644-0396                                   -     -
>                                                            -    -
>                                                             -  -
>   218 Westridge                                             --
>   Tallahassee, FL 32304                                    -
>   904-576-9442                                           -
>                                                        -
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