Fluorite, In den Dellen, Germany

Mineral Matters #399

I thought I might follow up yesterday’s post with another specimen from In den Dellen.

We are all used to fluorite as cubes or octahedrons, but in a few places, other unusual forms occur. This is one where the fluorite is spherical. I don’t know what causes it to form this way. If you know, let me know in the comments!

Also, there is a dendrite on the top of the sphere, as well as a neat rainbow.

The matrix of this specimen, like the one from yesterday, exhibits an orange fluorescence under longwave UV, and a pink fluorescence under shortwave. So likely sodalite and sanidine present. More Hidden Collection!

But the bonus with this one is that the colourless fluorite fluoresces purple-blue! I must get a photo taken of this.

Below: 4693 Fluorite, In den Dellen quarries, Mendig, Germany. Width of view 3mm. Click on the image for a higher resolution version.