Nuclear fast red (C.I. 60760; also known as Kernechtrot, and as
  McGee-Russell's calcium red) is often used as a pink or red
  counterstain that shows the nuclei of cells. Typically, it is 
  used as a 0.1% solution in 5% aluminium sulphate, which should
  make a "mordant" dyeing solution comparable to alum-haematein,
  alum-brazilein or alum-carminic acid. Opinions vary greatly
  about the value of alum-Kernechtrot as a nuclear stain, and
  I would like to pick the brains of the many HistoNetters who
  have used or tried to use this dye. Good and bad results may be 
  due to  differences in dye batches or to different techniques of
  application. It seems to me that trustworthy supplies of this 
  supposedly simple red/pink nuclear stain should be widely available
  to all who want to stain nuclei red or pink. 

  Searches of the scientific literature are disappointing, because
  the names of simple counterstains do not figure in titles of papers
  or in lists of keywords. My gut feelings (partly HistoNet-derived)
  are that (a) nuclear fast red is widely used, and (b) there are
  both happy and unhappy campers. 

  Please tell us of your experiences with this dye. It seems to me
  that it's a strong candidate for standardization and certification,
  and I intend to suggest it as a new certifiable dye at the June
  meeting of the Biological Stain Commission. In particular, say
  where you obtained good or bad dye, and if you have deviated from
  the "standard" ratio of dye:aluminium in the working solution.
  Reply to me alone or to the whole HistoNet community, as you see 
  fit. If there are lots & lots of off-list replies, I'll send in a
  general review of people's opinions in a week or two, as is often
  done. 

 John A. Kiernan,
 Department of Anatomy & Cell Biology,
 The University of Western Ontario,
 LONDON,  Canada  N6A 5C1
   Phone: (519) 679-2111
   FAX (Department): (519) 661-3936
   E-mail: kiernan@uwo.ca