Fluorite on Calcite
Gaskins Mine
Minerva Oil Company
Pope County, Illinois
9.11 cm x 7.24 cm x 6.53 cm
Here is a rare Fluorite specimen from Illinois.
This amazing Fluorite and Calcite specimen comes from the Gaskins Mine, Minerva Oil Company, Pope County, Illinois.
Where do I begin to describe this amazing specimen.
It was mined sometime in the early 1970's. This mine was only open for a few short years.
This rare color combination with it's longwave and shortwave fluorescence,
was only found in a small area of this mine.
The specimen consists of about 4 fluorite rhomb crystals but only two can be seen on display.
They sit on top of a few large calcite crystals which actually act as a perfect base for the piece.
There is also one small galena crystal embedded in the back of the specimen,
upon close inspection you can tell that this entire specimen
was removed from the face of a very large galena crystal.
The larger of the two fluorite rhombs that make up the focal point of the specimen measures 5.2 cm.
This is 100% natural and has not been fracture filled, will leave that up to the new owner if they wish.
The fluorite is 99% pristine, there is only one small cleave (barely visible)
on the top edge of the smaller front facing Rhomb.
What may look like damage to the large Rhomb is not,
looks like either an odd termination, etching or a re-healed area.
It has the most amazing color zoning that you will find from Illinois Fluorite.
The inner or first generation fluorite appears pinkish purple/ magenta, almost red in color in some lighting.
The outer or last generations appear to be colorless or white, but upon very close inspection, it is pale blue in color, which can be seen from the rear.
It is very interesting to see the 45 degree turn in the smaller intergrown crystal
whose core matches the turn.
Most Illinois fluorite has little or no fluorescence, however this one has very strong fluorescence.
Under longwave UV light it is a very bright bluish purple color,
as strong as most English Fluorite.
Under shortwave UV, the fluorite appears to glow very pale blue or even white.
The calcite that the fluorite sits on, glows both orange and red showing two generations of growth.
Overall a museum quality specimen of this amazing rare Illinois Fluorite.
