Sir Humphry Davy proposed that this then-unknown substance be named fluorine from fluoric acid and the -ine suffix of other halogens.
This word, with modifications, is used in most European languages; Greek, Russian, and some others (following Ampère's suggestion) use the name ftor or derivatives, from the Greek φθόριος (phthorios, destructive) .
Frémy's former student Henri Moissan persevered, and after much trial and error found that a mixture of potassium bifluoride and dry hydrogen fluoride was a conductor, enabling electrolysis.
It replaced earlier and more toxic compounds, increased demand for kitchen refrigerators, and became profitable; by 1949 Du Pont had bought out Kinetic and marketed several other Freon compounds.
Polytetrafluoroethylene (Teflon) was serendipitously discovered in 1938 by Roy J.
Fluorite, the primary mineral source of fluorine which gave the element its name, was first described in 1529; as it was added to metal ores to lower their melting points for smelting, the Latin verb meaning "flow" gave the mineral its name.
Proposed as an element in 1810, fluorine proved difficult and dangerous to separate from its compounds, and several early experimenters died or sustained injuries from their attempts.