If I understand this answer and this comment correctly, minerals like calcite, fluorite, and apatite are "commonly associated with (Rare Earth Element) REE deposits", and like some REEs also fluoresce when exposed to UV light. But the intrinsic fluorescent properties of those minerals are not caused by REEs.
Is this just a pleasant coincidence; the presence of one fluorescent mineral is often associated with the presence of another fluorescent mineral even though their fluorescence mechanisms are different?
Or do minerals like calcite, fluorite, and apatite tend to fluoresce because they contain REEs, thus observation of their fluorescence is a direct indicator of the presence of REEs? Or do REEs only modify the color of their fluorescence, but not necessarily cause it?