On Mon, 15 Apr 2002, Philopena, Jennifer wrote:
> We've been ... processing to paraffin ...

Paraffin processing extracts fat. The mentions of calcium
in your email relate to preserving phospholipids in
frozen sections. Fat is not a phospholipid, but it too
is preserved only in sections of tissue that has not been 
passed through organic solvents. 
----------------------------------------
John A. Kiernan
Department of Anatomy & Cell Biology
The University of Western Ontario
London,  Canada   N6A 5C1
   kiernan@uwo.ca
   http://publish.uwo.ca/~jkiernan