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"Rainbow" assortment of longwave UV reactive minerals

As all experienced fluorescent minerals collectors know, shortwave UV is the wavelength under which there's the greatest variety of fluorescent colors in UV reactive minerals, and many either fluoresce only under shortwave, or are at their best under this wavelength.

Getting an assortment of minerals that fluoresce in all the seven colors of the visible light spectrum is quite challenging, even in the case of shortwave UV reactive minerals; but it's incredibly harder to do so with longwave UV reactive minerals. So I gave myself the challenge of finding minerals that fluoresce brightly in all the colors of the spectrum under LW. It took a long time to find them all, especially a violet fluorescing one (violet fluorescence, especially a bright response, is pretty rare under longwave); but I did it! Taking the photo was quite challenging too; had to snap many, with different combinations of longwave UV + white light (almost impossible to get a correct color rendition of blue fluorescing fluorites under longwave; without some white light added, they look purple, and lack detail). It's impossible to get them all properly exposed; to avoid ending up with the brightest two being overexposed (the wernerite and the willemite), I had to slightly underexpose all the others. Here's the list of the specimens shown:

Cream-white, center :

Fluorite; Flamborough Quarry, Hamilton, Ontario, Canada

13,3 cm X 9,1 cm X 6,9 cm


Violet : Fluorite; Bessó mine (Sant Antoni Mines), Ulldemolins, Priorat, Tarragona, Catalonia, Spain

8,7 cm X 6,1 cm X 5 cm


Dark blue : Fluorite ; Mont-Tremblant area, Québec, Canada

7,9 cm X 4,2 cm X 3,9 cm


Light blue : Unknown – Grenville-Sur-La-Rouge, Québec, Canada

8,6 cm X 5,4 cm X 3,9 cm


Green : « Apple green » willemite ; Franklin Mining District, Sussex County, New Jersey

6 cm X 3,1 cm X 0,9 cm


Yellow : Wernerite ; Grenville-Sur-La-Rouge, Québec, Canada

9,6 cm X 6 cm X 2,8 cm


Orange :

Hackmanite; Davis Quarry, Dungannon Township, Hastings Co., Ontario, Canada

8,8 cm X 4,9 cm X 5,4 cm


Red :

Strontian aragonite; Boccheggiano mines, Montieri, Grosseto Province, Tuscany, Italy

7,7 cm X 6,3 cm X 3,9 cm

Shown in visible light in the second picture below.

Longwave UV

Visible light.


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