Manganaxinite {Ca2Mn2+Al2BO(OH)(Si2O7)2}:
FL Crimson SW
Willemite {Zn2SiO4}: FL Green SW
Calcite {CaCO3}: FL Red-Orange SW
The specimen shown above came from the collection of a Hungarian miner
who worked at the Picking Table at Franklin (the actual picking table, not
the magazine by that name). The manganaxinite fluoresces a beautiful,
deep red in short-wave UV. It is similar to the fluorescence of calcite,
but not identical. The easiest way for the beginner to tell the
difference is by looking for the brief intense phosphorescence (BIP) or "flash"
of calcite when the lamp is pulled away or turned off. Manganaxinite
doesn't have this property. Manganaxinite also doesn't bubble when
exposed to hydrochloric acid.
There aren't any places left where you can field-collect manganaxinite anymore
as far as I know, with the possible exception of the Trotter Dump. Last
I heard they won't be having any more field trips there. Somebody found
a manganaxinite at a Trotter dig a couple years ago, at least that's what
other collectors told me.
Manganaxinite is one of those minerals that had a habit of occuring only
wherever someone would later decide to put pavement. Some very nice
minerals share this peculiar habit.
Not all manganaxinite is fluorescent. It's nearly impossible to tell
in daylight whether a specimen of this mineral will or won't glow in short-wave
UV.
Sometimes the manganaxinite has a sparkly, crystalline surface. Shown
below is a close-up of the above specimen in normal light:
I don't know offhand what the pink mineral is. It bears a superficial
resemblance to rhodochrosite.
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