Microcline & calcite from Franklin
Microcline (fl. Pale Blue SW)
Calcite (fl. Red-Orange SW)

Microcline is the Rodney Dangerfield of Franklin minerals.  It gets no respect.  It isn't a lead silicate;  it isn't unique to Franklin;  it doesn't even fluoresce that well, usually.

Most field collectors look upon boulders full of poorly-fluorescing microcline as nothing more than a tiresome obstacle to finding "the good rocks". 

Once in a while, though, there appears a specimen that actually fluoresces well in short-wave UV.  Even the most jaded collectors (except Fred) will stop and give it consideration.  The best grade of fluorescent microcline bears some resemblance to margarosanite in short-wave UV.

The above photo was taken using a Superbright, some Shop-Rite 400 speed 35mm film, an exposure time of 2 seconds, and an f-stop of 5.6. At that setting the photograph came out even brighter than you see here, but I adjusted the gamma correction downward on the scanned image to make it more true-to-life.  However, you're still seeing a bit of over-exposure here.

This piece is about five inches tall. It's still one of my favorite specimens. 

When people come down to the Buckwheat while I'm collecting, they often ask if they can find any "blue" on the dump. The above specimen is a fine example of what one can find.

Many pieces of microcline from the Buckwheat will fluoresce a weak burgundy to magenta color-- or not at all. Some of the microcline gives a pleasant, light pink color, but this is unusual.  A few collectors refer to this variety as "pink amazonite", even though the pink refers to the fluorescent color only;  amazonite is green in daylight, while "pink amazonite" is typically grey, making it neither pink nor amazonite.  Someday I may photograph a bit of this "pink amazonite".




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