Phlogopite, Afghanite, Calcite, with Mysteries - Afghanistan

This rock reminds me of our early days collecting in the Ilimaussaq Complex of Greenland. At that time we were finding dozens of fantastically glowing rocks where we had no idea of the IDs. Slowly over the years people smarter than I studied and ID'd the various minerals and we now have a pretty good handle on most IDs (but not all - not yet).

Afghanistan is at that stage. I'm confident of most IDs but some I simply have no clue. The primary mineral on this specimen is a multi-wave responding phlogopite. Under SW it fluoresces a bright yellow, shifting to a bright butterscotch under MW, and almost red under LW. This is very unusual for phlogopite - perhaps only 10% of the specimens I've handled respond thusly. Note that the matrix contains a lot of phlogopite also.

A little bit of calcite pops out, mostly MW. But the blue fluorescence is a total mystery to me. The opposite side has a couple of brightly fluorescent (orange) spots of afghanite.

This is probably one of the prettiest rocks I've seen under MW.

Shortwave and Midwave (click to see large images)

Longwave and White Light (click to see large images)

Longwave and White Light - Side 2 (shows the afghanite) - (click to see large images)

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