Have you any suggestions for labels that could be used during the staining process that would still be legible and won't come off in xylene?
(a) For slides with a frosted end: Use an ordinary (graphite) pencil. After coverslipping cover the pencil with a thin layer of clear nail polish or diluted (1:5 in toluene or similar) mounting medium.
(b) For plain slides, use a diamond-tip pencil directly on the glass. This is very permanent, but it's more trouble than frosted slides - something of an art, especially if you need to write quite a lot on each slide.
With both methods there's a risk of getting BITS (of either graphite powder or ground glass) on the sections. Graphite is worse, because it's black. It's therfore a good idea to put a piece of paper over most of the slide for protection while you're writing on the end.
John A. Kiernan,
Department of Anatomy & Cell Biology,
The University of Western Ontario,
LONDON, Canada N6A 5C1