We tried this about 20 years ago.  We bought coloured material (I think from
a cake decorating shop) cut them into strips approx 1mm wide and stuck them
together with molten wax to make a multicoloured layered effect.  Once you
cut the first millimeter away the colour changed.

Problems associated with this procedure was:
1    Ensuring the strips were in fact 1mm wide,
2    The embedder had to be very aware of ensuring the strips and tissue
were actually on the bottom of the mold in the same         plane.  Embeding
became considerably slower.
3    Often tissue blocks were less than 1mm thick and material was lost.
4    We found teaching trainees to "use their eyes and a little common
sense" was much easier and far less traumatic for all concerned.
Bill Sinai
Laboratory Manager
Tissue Pathology
ICPMR
P.O. Box 533
Wentworthville NSW 2145

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Subject: block trimming indicator


> Hi All,
> I have been asked if anyone knows of a technique which would show how far
a
> wax block has been trimmed before the cutting stage.Like most people we
> utilise knowledge and expertise to determine if the block has been trimmed
> in far enough.However,we have been asked to try and quantify the procedure
> for trainee's so that they are unable to trim too far into a block as
there
> would be a visual indicator present.
> Someone suggested if there was a coloured marker present in each block of
a
> soft material/wax which would indicate levels within the block and not
> effect the cutting properties of the block , one could embed it along with
> the tissue.
> I am looking for suggestions and hope someone in histoland might have come
> across such a method.
>
> Ian Clarke
> Histopathology/Cytopathology
> Craigavon Area Hospital
>
>