Ken Urban at Surgipath writes:

>>Surgipath has been producing its version of the Harris hematoxylin since 
1980. We have never used mercuric oxide in our formulation. Ingredients are 
printed on the label.<<

What then is a Harris hematoxylin? Traditionally the term "Harris" is used to 
denote alum hematoxylins oxidized with mercuric oxide, and "Mayer" for those 
oxidized with sodium iodate. (Gary Gill's formulations are Mayer 
hematoxylins.)

It would appear that the present definition of Harris hematoxylin is "any 
hematoxylin our Marketing Department wants called Harris hematoxylin"

Does it make a difference? I once encountered a situation where it probably 
did. About thirty years ago (gack!) in setting up the Engel-Cunningham 
modification of the Gomori trichrome stain for frozen sections of skeletal 
muscle, I found that our homemade iodate hematoxylin didn't work, while a 
sample of mercuric oxide hematoxylin purloined from the cytopathology 
laboratory did. I added mercuric chloride to the iodate formula and it worked 
fine.

Somehow "Richmond hematoxylin" never caught on.

Bob Richmond
Samurai Pathologist

P.S. "Questionnaire" is spelled with two n's. I am quite certain of this, 
having won (and almost lost) the Grade School Spelling Championship of the 
Archdiocese of San Antonio in 1951 (gack again) with that word.
How an Episcopalian got into that situation is another tale.