On Sun, 09 Sep 2007 19:59:47 -0400, Joseph Gwinn
wrote:

,;In article , Wes
,;wrote:
,;
,; I just finished reading the "bullseye mixture" in the 2nd Machinists Bedside
,; Reader and am interested in trying the color case hardening formula
,; described.
,;
,; It seems the author got a bit of cold feet later on about the use of barium
,; sulfate.
,;
,; So the question is how dangerous is trying the method? What should one do
,; to minimise risk? I see Skylighter has it at reasonable prices.
,;
,; Barium sulphate isn't poisonous, but the water-soluable barium salts
,;are quite poisonous.

Barium carbonate is slightly soluble in water. In fact one can convert
barium sulfate to barium carbonate by boiling in a solution of sodium
carbonate. This procedure is used in analytical chemistry.

Barium carbonate dissolves in dilute hydrochloric acid (as do most
carbonates). If you ingest barium carbonate the acidity of the stomach
will convert the barium carbonate to soluble barium chloride and you
are in big trouble.
,;
,;http://gsm.herston.uq.edu.au/radiolo...Agents/Contras
,;t.html
,;
,;Joe Gwinn