According to this page (see URL below) the ammon alum found in crystals is
described;

"Tawas Crystal Deodorants are 100% mineral salt. Ammon alum to be exact. It
comes from Bauxite ores in mountainous and volcanic areas in Asia. Ammon
alum is indeed a form of Aluminium, BUT unlike Zirconium or Chlorohydrate it
is perfectly safe as it does not enter the body as the molecules are far to
large to pass through the cell membrane."

So perhaps it is safe?

http://www.pages4women.com/article.asp?sectName=Organic+Lifestyle&ArtId=210

It goes on to say that it has been used in the Phillipines for centuries.

Marilyn

At 04:31 PM 1/12/04 -0700, Lynnet Bannion wrote:
>Lynda Bryson wrote:
>
>>Per Websters, alum is defined as: "any of various
>>double salts isomorphous with potash alum."
>>
>>
>*My* Webster's has this definition of alum:
>
>"A general name for a class of double sulfates containing aluminum and
>such metals as potassium, ammonium, and iron. Common or potash alum
>is used in medicine as an astringent and a styptic; in dyeing, as a mordant;
>in tanning, for restoring the cohesion of skins."
>
>If an item says "alum" it contains aluminum.
>
>    Lynnet
>
>