Recovered from fluorite or cryolite or fluorapatite

Usage examples of fluorine.

Actually, that makes sense: neutrons decaying into protons and pions would transmute some of the calcium to scandium, the oxygen to fluorine, and the carbon to nitrogen.

The more outrŽ science-fictional speculations about extraterrestrial biochemistries—silicon in place of carbon, chlorine or fluorine in place of oxygen, and so forth—were all very clever, but for various reasons they just didn't work.

To cite one case, a steroid that differs from the natural corticoids in possessing a fluorine atom attached to carbon-g is an unusually active glycocorticoid, ten times as active as the natural ones.

A few hours later, the somewhat chastened scientist admitted that he had also found two bottles of elemental fluorine, used to power the lasers which could zap passing celestial bodies at thousand-kilometre ranges for spectrographic sampling.

It sometimes appears combined with fluorine in chlorine trifluoride.

Polyvinylidene difluoride was a special polymer in that respect—carbon atoms were linked to hydrogen and fluorine atoms in such a way that the resulting substance was even more piezoelectric than quartz.

But there are abundant microbes on Zaranai that metabolize fluorides and release fluorine gas as a waste product.

Lithium five doesn't exist on Earth, or glucinium eight, or nitrogen fifteen or 'oxygen seventeen or fluorine eighteen or sulphur thirty-four - or thirty-five!

Even the halogens were still frozen across its flat top, thousands of square miles of fluorine ice with near-vacuum above.

Some other molecules--hydrogen fluoride, for example--might approach water in their ability to dissolve other molecules, but the cosmic abundance of fluorine is extremely low.

As pure fluorine was about the most vicious substance known to man, it was high on the list of prohibited materials - but, like the rockets which drove the penetrometers down to their targets, it was essential for the mission.