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And welcome!
And returning to your post, isn't calcium fluoride the naturally occurring form of fluoride - the stuff that's in the water that's naturally fluoridated? (I don't know - just thought that's what I had picked up from this thread.)
The "name" Fluoride applys to the reduced form of Fluorine, the chemical ion F-. Also any compounds containing Fluorine are considered fluorides.
Fluoride occuring naturaly in water is the ion F-. According to http : // www . env . gov . bc . ca / wat / wq / BCguidelines / fluoride / fluoridetoo-03 . html calcium compounds are added to water with too much natural Fluoride in it, as it forms Calcium Fluoride, which is insoluble, and forms a precipitate. So no, calcium fluoride is not the naturally occuring form in water.