2021-7-22 · 482547 1911 Encyclopædia Britannica, Volume 10 — Fluor-spar. . FLUOR-SPAR, native calcium fluoride (CaF 2 ), known also as Fluorite or simply Fluor. In France it is called fluorine, whilst the term fluor is applied to the element (F). All these terms, from the Lat. fluere, "to flow," recall the fact that the spar is useful as a flux in ...