Common Questions About Fluorescent Minerals – An FAQ Guide

Fluorescent minerals can be fascinating to those who discover these hidden treasures and they often raise various questions. Here are some common questions related to fluorescent minerals:

What are fluorescent minerals?

Fluorescent minerals are a specific type of mineral that exhibit the property of fluorescence when exposed to ultraviolet (UV) light. Fluorescence is a phenomenon where a material absorbs energy from a light source, typically in the UV range, and then re-emits that energy as visible light. This visible light is often of a different color than the absorbed UV light, creating a striking and vivid display of color. You can dive deep into the science of fluorescent minerals here.

What causes the different colors in fluorescent minerals?

The different colors in fluorescent minerals are primarily caused by the presence of specific impurities or activators within the mineral's crystal lattice.

• Impurities or Activators: Certain elements, ions, or compounds act as impurities or activators within the mineral. These impurities play a crucial role in determining the color of fluorescence. For example, manganese can produce orange fluorescence, while lead can yield blue fluorescence.
• Chemical Composition: The chemical composition of the mineral itself also influences the color of fluorescence.
• Wavelength of UV Light: The wavelength of the UV light used to excite the mineral can also affect the observed color of fluorescence. Different minerals respond to different wavelengths of UV light. Using longwave (LW), shortwave (SW), or midwave (MW) UV lights can lead to variations in the colors observed in the same mineral.
• Crystal Structure: The crystal structure of the mineral can influence the efficiency of fluorescence and the way the mineral emits light. This can impact the perceived color of fluorescence as well.

Collectors often find this diversity in colors to be one of the most fascinating aspects of fluorescent minerals.

Can any mineral fluoresce, or is it specific to certain minerals?

While many minerals do not fluoresce under ultraviolet (UV) light, there are certain minerals known for their fluorescence. Whether a mineral fluoresces or not depends on its chemical composition, crystal structure, and the presence of certain impurities or activators. 

Some minerals are more likely to exhibit fluorescence, and these include but are not limited to fluorite, calcite, aragonite, willemite, scheelite, hydrozincite, hackmanite, barite, autunite, scapolite.

How do you find fluorescent minerals?

Finding fluorescent minerals involves a combination of observation using ultraviolet (UV) light and some basic knowledge of minerals.

 

Grab a UV light source, a UV lamp or UV flashlight. There are different types of UV lights in the form of lamps or flashlights that emit lights at different wavelengths including longwave 365nm (LW), shortwave 255nm (SW), and midwave 310nm (MW).

Set up in a darkened room or space to maximize the visibility of fluorescence. Or if you’re out and about, grab a BBQ grill cover, dark blanket/sweater – some kind of dark covering to create a smaller, dark space. See photo below:

Shine the UV light on the mineral specimen and observe the fluorescence if there is any. Some minerals may exhibit phosphorescence, which means they continue to glow for a short time after the UV light source is turned off.

Important Note on Fluorescence and Identifying Minerals: Fluorescence is very unreliable in identification. It’s only used as an aid when dealing with rocks from a known locality.

Are UV lights safe? Are there any safety precautions needed when using UV lights for fluorescent minerals?

There is no need to be worried about using UV light, just make sure to use common sense safety precautions and you will be fine. Protect your eyes and skin when using UV light sources, avoid prolonged exposure. By following these safety precautions and being mindful of the potential risks associated with UV lights, you can safely enjoy the hobby of fluorescent minerals. Read below for some safety considerations. 

1. UV Radiation Hazard
   • UV lights emit ultraviolet radiation, which is invisible to the naked eye. Shortwave and midwave UV lamps can produce UV-C and UV-B radiation, which are more harmful than longwave UV-A light.

• UV radiation can damage the skin and eyes, leading to sunburn, skin aging, and eye irritation or damage.

2. Eye Protection
   • Always wear UV-blocking safety goggles or glasses that provide adequate protection against the specific wavelengths emitted by the UV light you are using. Never use sunglasses. Ordinary sunglasses do not provide sufficient protection and interfere with viewing.
3. Skin Protection
   • Apply sunscreen with a high SPF rating to any exposed skin, even if it's not directly illuminated by the UV light.
   • Cover exposed skin to minimize UV exposure.
4. Limit Exposure Time
   • Minimize the time you spend in close proximity to the UV lamp. Shortwave and midwave UV lamps should not be used continuously for extended periods unless there is a UV blocking shield in front of the display (like OP3, which we talk about here towards the bottom of the post).
5. Children and Pets
   • Keep children and pets away from UV lights and the minerals you are examining, as they may be more sensitive to UV radiation.

Are there any famous fluorescent mineral locations or mines?

Greenland

Greenland is one of the world's last mineral frontiers. The Ilimaussaq Complex has an abundance of rare earth minerals and is now a world famous locale for fluorescent minerals. Some of the stuff you can find here includes tugtupite, sodalite, polylithionite and more.

Franklin and Sterling Hill Mines, New Jersey, USA:

These mines in Franklin and Ogdensburg, New Jersey, are renowned for their rich deposits of fluorescent minerals, including esperite, hardystonite, margarosanite, willemite, calcite, and many others. The area is often considered the world's premier location for fluorescent mineral collecting.

Langban, Sweden:

The Langban mine in Sweden is known for a variety of fluorescent minerals, including svabite, sphalerite, margarosanite and others. It's a classic location for fluorescent mineral enthusiasts.

Lake Superior, Upper Peninsula, Michigan, USA:

This area is a great place to start hunting for fluorescent minerals. You can find “Yooperlites”, which are essentially just fluorescent sodalite rocks all along the shore of the beach. All you need is a longwave light (365nm) and just shine it on the ground while walking along the shore.

Are there any online communities or resources for fluorescent mineral enthusiasts?

Yes, there are a bunch of very active online communities and resources dedicated to fluorescent mineral hobbyists. These communities have tons of information and resources to help.

• Nature's Rainbows (noncommercial site)
• The Fluorescent Mineral Society (FMS)
• Fluorescent Mineral Subreddit
• Fluorescent Mineral Facebook Group (very active)
• Fluomins 
• YouTube