Introduction
There are a number of minerals and localities in Nova Scotia that produce fluorescent and phosphorescent minerals. The optical properties of some of the specimens can be quite striking, with a bright response to ultraviolet light. Calcite is the most common fluorescent mineral in the province. Several different colors can be found and sometimes in specimens that are attractive even in visible light. Many rarer fluorescing minerals have also been found, or more common minerals that rarely fluoresce. In addition, several species have been found to phosphoresce.
This page is not meant to an exhaustive of all colors from all localities. I'm more interested in the mineral species that fluoresce with perhaps a few examples if different ones exist. Some of the instances listed below are reported for the first time. When this page was created it was the first collected description of fluorescent minerals from Nova Scotia, however it was enhanced by collector Jacques Poulin of Quebec who made some very thorough investigations in the early 2000s. It continues to grow as new finds are made.
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There are other ways to add energy to a mineral to make it produce visible light. Thermoluminescence is when the mineral produces light when heated. And triboluminescence is when a physical force (ex. striking with a hammer) is the source of input energy. I am not aware of either of these reported for minerals from Nova Scotia, but they may be present.
The Minerals
The two tables below summarize the species and colors of fluorescence and phosphoresence that have been found in Nova Scotia. It has been quite a while since I looked at the UV response of my collection, and at the time, I did not note whether the response was for short wave (SW), medium wave (MW), or long wave (LW). I hope to fill in much of these tables in the near future.
Table 1: Fluorescent mineral species from Nova Scotia and colors observed.
Table 2: Phosphorescent mineral species from Nova Scotia and colors observed.
Analcime
Fluorescent analcime was discovered by local collector Terry Collett. The analcimes were from a fresh fall at Wasson's Bluff. Not all of the analcimes fluoresced, but those that did tended to have copper crystal inclusions. Although the copper crystals themselves won't fluoresce, there certainly seems to be some relationship between the two. The fluorescence spectrum shows a broad peak from about 430-510 nm, peaking at 480 nm.
Anhydrite
Very fluorescent anhydrite can be found near Iona. Here somewhat crystalline material can be found that fluoresces an intense yellow, with a much paler phosphorescence. Massive anhydrite at other locations, including Cheverie also fluoresces yellow, but it is much paler in comparison.
In measuring the spectra of many of the minerals on this page, I was surprised to learn that the spectrum for the anhydrite and the Springville aragonite are nearly identical. Though the colors in the photos on this page are not the same, there may be some problems with the photos (which were taken at different times). In both cases the peak is very broad, with a half-maximum ranging from roughly 475-575 nm.
Apatite
At Boylston, a couple specimens of apatite are known. The apatites are small and very pale pink in color. Although they are tabular in shape, they are extremely difficult to spot visually in daylight. However under UV, they reveal their presence by fluorescing pinkish/purplish-white (the purple seems accentuated in the photos below). Apatite often contains rare-earth elements that fluoresce. I'm not sure if that is the case here.
Aragonite
At Springville very slender aragonite crystals are found in limestone. They both fluoresce and phosphoresce an intense and vibrant yellow color. The brightness is among the best from the province. The color and intensity of the fluorescence, the phosphorescence, and the environment are all consistent with hydrocarbons being the activator. This is well known for other aragonites worldwide, but has not been verified in this instance.
Barite
Coxheath has produced a small number of specimens of barite and calcite. In these specimens the calcite fluoresces red, and the barite fluoresces and phosphoresces a pale greenish color, making for an interesting combination. A similar combination, with similar coloring but much brighter barite has been found in Colchester County. In this case, however, only an outline of each barite crystal can be seen. This produces a very interesting visual effect.
Calcite
One of brightest fluorescents in the province is the calcite from the sandstones between Cheverie and Walton. Here the calcite, which generally forms white scalenohedrons, fluoresces an intense orange-red. The fluorescence in this case is due to manganese ions (Mn+2). The ions are present as an impurity in the calcite in a very low concentration. The manganese in this case is called the activator, because it is responsible for the fluorescence. The calcite is just a host material for the manganese. Interestingly, if the manganese content of a calcite crystal is too high, it will not fluoresce - just the right amount is very important.
Further down the shore at Tennycape, some of the calcite crystals fluoresce a pale orange with a tinge of yellow. The pale yellow remains as a phosphorescence after the ultraviolet light has been removed. Across the Minas Basin to McKay Head, drusy calcite crystals can be found that fluoresce and phosphoresce a pale white.
Calcite is sometimes found associated with zeolites in the basalt at a few Bay of Fundy localities, including Harbourville and Cape D’Or. At those two spots calcites have been found that fluoresce and phosphoresce a quite nice greenish yellow. Also at Cape D’Or calcite, with a stilbite coating, has been found that fluoresces yellow.
The plot below shows the fluorescence spectra of four different calcite samples from Nova Scotia. The absolute intensities are not relative - varying exposure times were used to collect the data. The sharp peak at 435 nm is not real - it is an artifact of the measurement system. We can see that all of the curves share three peaks of varying intensity. These are at ~490 nm, 605 nm, and 640 nm.The Harbourvile and Rainy Cove samples each have only one activator each, while the New Brittain Road and Eureka Mine samples show all three peaks. These last two localities are very close geographically, but I'm not sure if they have any geological relationship.
Carraraite
A single specimen of the ultra-rare mineral carraraite was found and identified from between Cape D'Or and Cape Spencer. It fluoresces dull yellow.
Cerussite
Cerussite crystals from the Dunbrack Mine fluoresce yellow.
Corundum
Purple corundum crystals from Frenchvale fluoresce red. Though I have not measured the spectrum, red-fluorescing corundum is known from other localities, with a peak at ~693 nm, where the activator is Cr3+.
Fluorite
At least some of the fluorite from Chester is phosphorescent. One specimen with small crystals on quartz phosphoresces white while the quartz fluoresces red. This webpage (https://www.fluomin.org/uk/fiche.php?id=628) mentions a 680 nm fluorescence, which would be red, caused by Fe3+. It would be interesting to look at this fluorescence in the spectral domain.
Gmelinite
Pictured below is a specimen of gmelinite on very pale amethystine quartz that fluoresces brightly lime green. It is from Amethyst Cove and consists of one large crystal surround by many smaller crystals. It has not been tested, so it could conceivably be chabazite, but the habit and surface features suggest gmelinite. I had previously thought it might be coated by hyalite opal, but under magnification, there does not seem to be another mineral present. Also note the top-right corner of the crystal is abraded and that area does not fluoresce, suggesting that only the outermost surface of the crystals contains the fluorescent activator.
Typically, fluorescent spectra tend to be very broad with only one or two peaks. This specimen gives a spectrum with four peaks. Comparing to the spectrum obtained from meta-autunite (a uranium mineral) from near Timberlea, we can see that the peaks match very well, except they are shifted to shorter wavelengths. This indicates that the activator is uranium (or more accurately the uranyl ion), with the energy levels modified by the surrounding zeolite. The peaks are also skewed such that wavelengths longer than each peak drop in intensity less than those shorted than the peak. I'm not sure what that might say, if anything, about the mineral. The peaks for aqueous UO2 are also at shorter wavelengths than meta-autunite (Geipel et al. 2000).
Hydrozincite
Another interesting combination is hydrozincite and calcite from Colchester County. Again, the calcite fluoresces red, and the hydrozincite fluoresces an intense bluish white. The combination is difficult to find, but even the hydrozincite on its own is nice due to the bright fluorescence. In visible light it forms white coatings on shale.
Meta-autunite
Meta-autunite is reported from many localities in the South Mountain Batholith. It is inherently fluorescent. The specimen shown below was found along Hwy 103 between Bayers Lake and Timberlea. The fluorescent spectrum (plotted in the gmelinite section) is interesting and shows several peaks. They wavelengths of those peaks match very well with the literature (Baumann et al. 2007).
Powellite
Another mineral reported from the skarns is powellite, listed in the provincial Mineral Occurrence Database as occurring at McMillan Brook. This mineral is typically fluorescent, though I'm not positive about this instance.
Pyromorphite
Most pyromorphite crystals from the Dunbrack Mine fluoresce orange and yellow. Fluorescence in pyromorphite is not widely reported but is known from other localities such as the Roughton Mine in Cumbria, UK and others (Robbins 1985).
Quartz
Quartz from the Chester Sand and Gravel quarry fluoresces red. This webpage (https://www.fluomin.org/uk/fiche.php?id=628) mentions a 680 nm fluorescence, which would appear red, caused by Fe3+. That webpage gives the source of that information to be Luminescent Spectra of Minerals, Boris S. Gorobets and Alexandre A. Rogojine, Moscow, 2002, but I have not seen this book. It would be interesting to look at the fluorescence of the Chester material in the spectral domain.
Scheelite
A bit further along the Eastern shore is the Moose River tungsten deposit mined about century ago. The ore was scheelite which is a well known, very fluorescent mineral. Scheelite is also known from Lime Hill and there is a published photograph, copied below, showing its fluorescence.
Strontianite
White druses and balls of strontianite from Lake Enon fluoresce and phosphoresce yellow.
Thaumasite
A very localized find of thaumasite at Cape D'Or was found to produce a dull fluorescence.
Willemite
A very rare mineral from Nova Scotia is willemite, from the Kirkmount Prospect. To my knowledge, it has only been found in a drill core taken from that prospect. The willemite is highly fluorescent.
Conclusions
Fluorescence is a great way to study to explore some optical and physical properties of minerals. There are undoubtedly more examples from Nova Scotia and every new mineral occurrence should be checked to identify them. However, even the ones that are known are varied and interesting.
Acknowledgements
Special thanks to all those fluorescent buffs out there. These include Dick McAllister for the hydrozincite, Liz Fodi for the pyromorphite, Terry Collett for the analcime and anhydrite, Doug Wilson for the Boylston apatite, and Doug Bowes for the willemite. Thanks also to Emilie and Ron Kendig (Emnron on Ebay, aka Nature's Window) for use of the Moose River scheelite photos. Thanks also to Jacques Poulin for much additional information. Particular thanks to Doug Bowes (aka The Amazing Dr. Flame-o) and Fred Walsh for their endless enthusiasm for fluorescent minerals - and who inspired this page.
References
Baumann, N., Arnold, T., Massanek, A. (2007) TRLFS fingerprints of uranium phosphate minerals. Wissenschaftlich-Technische Berichte, Institute of Radiochemistry, Annual Report 2006, pg 68-68. [Online 2021]
Chatterjee, A.K. (1977) Tungsten Mineralization in the Carbonate Rocks of the George River Group, Cape Breton Island, Nova Scotia. Nova Scotia Department of Mines, Report 77-7. [Online 2018]
Geipel, G. Bernhard, G., Nitsche, H. (2000) Spectroscopic properties of uranium(VI) minerals studied by time-resolved laser-induced fluorescence spectroscopy (TRLFS). Radiochimica Acta, 88, 757-762.
Robbins, M. (1985) Fluorescent Forum: Fluorescence in Pyromorphite and other Lead Apatites. Rocks & Minerals, 60(6), 293-296.
Sangster, A.L. (1986) Willemite and Native Silver Occurrences, Kirkmount, Pictou County, Nova Scotia. Geological Survey of Canada, Paper 86-1A, pp. 151-158. [Online 2018]
Sabina, A.P. (1964) Rocks and Minerals for the Collector - Bay of Fundy Area. Geological Survey of Canada, Paper 64-10. [Online 2018]
"UK Fluorescent Mineral Occurrences", The Russell Society, 2003.
Mineral Occurrence Database, Nova Scotia Department of Mines.
Disclaimer: This page is intended for information purposes only. The localities described are not necessarily open to collecting and are not necessarily safe.