Minerals which are capable of this reversible color change by exposure to UV (or other energy sources), without any change in their essential composition, are said to be tenebrescent
Posted on February 13, 2023
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Over the years I've had requests for lighting controllers that would allow us to remotely control our different wavelength lights.
Posted on February 13, 2023
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This needs to be said. Over the years a few disreputable sellers have been marketing a little 4/6 watt shortwave light for fluorescent minerals.
Posted on February 13, 2023
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Helvetia. Just the name conjures up all sorts of thoughts, images and expectations. Goddesses, Switzerland, and perhaps even hell itself. Who knew what awaited us in the heart of the Arizona desert?
Posted on February 13, 2023
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The Midwest Chapter of the Fluorescent Mineral Society (FMS) held its first annual meeting at the Ben E. Clement Mineral Museum in Marion, Kentucky, on Saturday, September 16th.
Posted on February 13, 2023
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I cancelled my plans to take the grandchildren to the fall Franklin Mineral Show. As a Plan B, I decided to go to the Midwest Chapter of the Fluorescent Mineral Society (FMS) meeting and fieldtrips near Cave-in Rock, IL
Posted on February 13, 2023
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It was officially spring and time to get out to collect fluorescent minerals.
Posted on February 13, 2023
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I have a nickname for esperite pieces – I call them “hard rocks”, very hard to photograph. Our rocks “glow” like a lightbulb.
Posted on February 13, 2023
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Many minerals exhibit an “afterglow” when the UV light is turned off. This glow can last for milliseconds or hours depending on the mineral.
Posted on February 13, 2023
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Recently I posted a question about Afghan sodalite (hackmanite) after reviewing the MinRec article about Sar-E-Sang. Someone reminded me that there was a large discussion on this topic last year. I dug out that discussion and copied it here to the blog. This is one reason we created Nature's Rainbows - to capture these excellent discussions.
Posted on February 13, 2023
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Tenebrescence of Greenland sodalite is amazing. This is a piece of a deeply tenebrescent sodalite.
Posted on February 13, 2023
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Tenebrescence is when minerals change color when exposed to sunlight, also known as reversible photochromism.
Posted on February 13, 2023
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