FMF - Friends of Minerals Forum, discussion and message board

[Mark Ost]

One more fluorescent piece from Arizona with willemite, calcite and really pretty blue hydrozincite. Visible in SW UV. The piece also has sphalerite, visible in LW, which has an extreme afterglow of an intense orange hue.

[Mark Ost]

Here are some pictures of a highly unusual mineral sample that showed up at my door step from an old friend. He is now a retired Forest Service Supervisor who was stationed in the Upper Peninsula of Michigan.

The samples are of a mineral known as Chlorastrolite, a variety of pumpellyite. As far as I know these are found in only one known location on earth, the UP of Michigan. Usually as rounded beach sediment. This is also the official gemstone of Michigan. All are small in the .5 cm range.

The largest is in the Smithsonian collection, measuring 4 cm by 8 cm. Pictured is the turtle back exterior pattern of three samples and one picture of the radiating, color zoned structure of a cross section of the interior of the mineral. I hope you enjoy these small but unique mineral samples that I was fortunate to receive.

[Mark Ost]

Adamite and Smithsonite on a limonite matrix. Will post micro-photos at a later time. sample is fluorescent in SW and MW

[Mark Ost]

Same piece under MW fluorescent light

[Mark Ost]

Stibnite and Calcite from China.

[Mark Ost]

Azurite so deep blue it is almost black. The picture does not do this piece justice as to the depth of color.

[Mark Ost]

Been a bit of time since I was able to play with the microscope but have a few free days now so this is some of the work from last night.

[Mark Ost]

Celestine and Sulfur from Italy and Roselite from Morocco

[Mark Ost]

Here is an unusual offering. Hydroxylherderite from Pakistan. A spectacular blue in SW UV. Not sure what the yellow green mineral is.

[Mark Ost]

Rubellite From the FSU

[Mark Ost]

Brazilian Elabaite

[Mark Ost]

Here is an interesting piece I just received. It is quartz with zoned fluorapatite crystals and a bit of siderite on the termination of the quartz. The fluorapatite displays almost Terlingua type luminescence dependent on the wave length of the excitation light. The faces fluoresce a blue hue in short wave and a pinkish hue in medium wave. It also displays an after glow subsequent to exposure to SW. The siderite has a dull orange fluorescence that does photograph well.

[Don Lum]

Nice specimen, Mark. Thanks for demonstrating the fluorescence.

Don

[Mark Ost]

Thanks Don. it deserves a better photographer than I am, but you can only do so much!

[Mark Ost]

Here are a couple of pictures demonstrating the ultra violet portion of the sun's spectrum causing a Rogerly fluorite to fluoresce, created by, of all things, a slit in my garage door rail. I noticed the slit created a diffraction grating due to the angle of the sun light passing through the slit and splitting the light into a spectrum on a piece of wood. What to do? Run and get your most sensitive fluorite and place it in the blue indigo section of the spectrum.