FMF - Friends of Minerals Forum, discussion and message board

[vic rzonca]

A bezoar is a lump of hardened, undigested material found in the gastrointestinal tract of deer, antelope, goats, oxen and llamas. It forms when layers of calcium and magnesium phosphate build up around a small bit of plant fiber or a pebble. Stomach contractions squeeze and smooth it into a roughly round shape. Bezoars had value because they were believed to have the power of a universal antidote against any poison. Tradition held that a drinking glass which contained a bezoar would neutralize any poison poured into it. Not recommended by nine out of ten physicians, for poisonings.

[Tracy]

humans form bezoars too...but not ones made of apatite. :)

[cascaillou]

we can also (painfully) form whewellite

[alfredo]

Yes, I know the feeling, unfortunately, having produced a whewellite crystal aggregate myself once in Tucson. Once was enough.

A good friend in the Netherlands donated me 2 struvite crystals his urinary tract had produced. Lucky him - Struvite crystals have much less sharp edges than whewellite crystals do.

Now I wonder what determines whether ones‘ kidneys will produce whewellite or struvite or some other mineral? Diet? pH? bacteria?

And back to Vic‘s original post about bezoars... How common are they? I‘ve never seen one, but then again can‘t say I‘ve spent much time messing about in the entrails of ungulates either.