UserX
It's funny. The MUCH cheaper Ozarka spring water has .05 mg/liter in it.
I was paying 3 times the money for something that was bad for me. Go figure.
Of course Ozarka does make a fluoridated version which has .72 mg/liter in it. That's astronomical.
Calcium Fluoride (fluorite) is the compound that occurs naturally in minute amounts that is supposed to be normal to ingest with water, but it's not even .01 ppm from what I've seen in nature. Sodium fluoride has a different structure to it since sodium has one valence electron and fluoride has 7, so the two bond to form a stable compound.
Calcium has 2 valence electrons so it takes two fluoride atoms to stablilize the compound and I'm thinking in this case Calcium has a different effect on fluorine. But I could be wrong. It might render it inoperative in this compound, as opposed to sodium fluoride. Just speculation.