• billfowler1989

Alabama Fluorescent Minerals

Since this site doesn't seem to contain very many photos of mineral specimens from Alabama, I thought I would contribute a few of my own. I have omitted those that contain common activators (e.g., divalent manganese and uranyl ion) in situations where better examples of the pertinent mineral/activator combination are available from elsewhere. I have been field-collecting local fluorescent minerals here in Alabama for several decades. Unfortunately, the opportunities for collecting them are no longer what they used to be.


Bill Fowler



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1. Petrified wood, Marion Co., AL, abandoned coal mine near Brilliant, AL -- This petrified wood specimen bears a coating of fine, druzy quartz crystals that fluoresce a butter-yellow color under either LW or SW UV. Oddly, I have other specimens of this material that exhibit both fluorescing and nonfluorescing zones of quartz crystals on the same specimen. Shown here is the view under SW UV and in ordinary room light. Specimen mass = 107 g. Approximate dimensions = 9x6x2 cm.






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2. Fluorite and strontianite on limestone, City of Huntsville, Madison Co, AL -- From a now-closed construction site in Huntsville, this piece of limestone contains an amber-colored fluorite that fluoresces an attractive yellow-white color and strontianite that fluoresces in bluish-white. Both minerals fluoresce about equally well under either LW or SW UV, and both are moderately phosphorescent, especially under SW UV. The views under SW UV and under room light are presented here. This specimen also displays some purple fluorite, whose fluorescence is seen to be much weaker than that of the amber fluorite. Specimen mass = 144 g. Approximate dimensions = 8x5x3 cm.







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3. Calcite, AL Highway 75 road cut, Blount Co., AL -- This piece fluoresces strongly enough under either LW or SW UV to hold its own in displays that contain my brightest fluorescers from around the world. Note that the array of colors produced is slightly different under LW versus SW UV. Note also that both fluorescent and nonfluorescent zones are evident in the specimen and that some of the fluorescence appears to follow certain linear seams or fracture planes within the crystals. These characteristics are typical of organically activated calcites, which are widely abundant in limestone deposits in roughly the northern half of Alabama. I enjoyed several trips to this location until I was ultimately evicted by a state trooper. Specimen mass = 140 g. Approximate dimensions = 7x6x3 cm.









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4. Barite, Bibb Co., AL, near Six-Mile Creek -- This specimen was collected near an abandoned barite mine that is located on the banks of Six-Mile Creek in an area that locals refer to as "The Sinks" .Interestingly, the abundant barite that is still to be found at the mine site exhibits little or no fluorescence. But I found the occasional barite specimen eroding out of the drainage ditches along the lengthy trail leading into the mine area. Those specimens turned out to be by far the brightest-fluorescing barites that I have ever seen from anywhere. One of them is depicted here under SW UV and under ordinary room light, but it fluoresces equally well under LW UV as well. These barites show up nicely in any fluorescent display. Specimen mass = 238 g. Approximate dimensions = 7x6x5 cm.







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5. Travertine or flowstone (calcite), Madison County, AL, I-565 road cut -- Fluorescent travertine is common all over northern and central Alabama, but much of it is only modestly bright in UV light. Hence, I often don't even bother to collect it when I find it. This piece, however, is exceptionally bright and clean. Like many of Alabama's fluorescents, it does about equally well under either LW or SW UV, and it also phosphoresces under both wavelengths. Shown here are the SW UV fluorescence and the room-light appearance of the specimen. Specimen mass = 194 g. Approximate dimensions = 8x7x3 cm.







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6. Selenite (gypsum), Conecuh Co., AL, near Castleberry -- This selenite is not especially bright, but the eerie bluish-greenish-white glow is, to my eye, a thing of beauty and fascination nonetheless. The observed fluorescence is a bit stronger under SW than under LW UV, and I never get tired of watching the slow decay of its SW phosphorescence, as though the stone's essence, once brought to life by the SW UV beam, stubbornly refuses to die when the light is extinguished. Shown here are the SW UV fluorescence and the daylight appearance of the specimen. I also included my feeble, largely unsuccessful attempt to capture its beguiling phosphorescence. Specimen mass = 142 g. Approximate dimensions = 10x5x3 cm.









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7. Fluorite, Marshall Co., AL, near Guntersville Dam -- This specimen was found in limestone riprap that was quarried nearby in now-closed quarries in Marshall County, AL. It consists mainly of gray limestone and nonfluorescent white or light-pink crystalline dolomite that surrounds a patch of amber fluorite. As shown here, the fluorite fluoresces in a strong yellow-white color under both LW and SW UV. But as the SW photo reveals, there is also some blue SW fluorescence around the periphery of the fluorite, possibly due to another activator in the fluorite or to the presence of a different mineral altogether (e.g., calcite). Specimen mass = 334 g. Approximate dimensions = 10x7x5 cm.









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8. Calcite, unknown quarry, Jefferson Co., AL -- This fine example of fluorescent Alabama calcite was found in limestone riprap in the City of Birmingham and was likely quarried somewhere nearby, as there are many limestone quarries in the area. It illustrates the rich and subtle mix of pastel colors that one typically sees in so many of Alabama's fluorescent calcites, and it is exceptionally bright. Shown here are the LW and SW UV fluorescences and the view under room light. Specimen mass = 218 g. Approximate dimensions = 7x6x4 cm.








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9. Pegmatite/Feldspar, Coosa Co., AL -- Here is a feldspar-rich specimen of pegmatite that was found on a remote logging road where a bulldozer had broken through a steep bank to make the road. The bank contained a large deposit of eroding pegmatite, much of which sported this beautifully fluorescent feldspar. I have no idea exactly what kind of feldspar this is -- maybe someone else can tell me. It fluoresces under both LW and SW, but only the SW version appears here, along with the room-light image. The slight reddish hue that appears in the otherwise bluish flurescence is not source reflection or a photographic artifact; it is a genuine fluorescence response that is probably caused by the presence of a minor second activator (e.g., divalent iron?) in some parts of the stone. Specimen mass = 270 g. Approximate dimensions = 9x8x4 cm.






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10. Calcite, AL Highway 75 road cut, Blount Co., AL -- I couldn't resist the urge to throw in one last Alabama calcite specimen. This is a roughly rectangular block of limestone with a calcite vein running diagonally through it, a pattern that I find especially appealing. The colors and color variations are typical of specimens from widely distributed locations around the state. Both LW and SW UV fluorescences are shown, along with a room-light photo. Specimen mass = 755 g. Approximate dimensions = 13x8x6 cm.