Collecting Fluorescent Minerals - The Basics, Where to Find Them, and How to Collect Them
Rock collecting is a pretty easy hobby to get into - buy a hammer, find a pile of rocks, and you're rock collecting. Fluorescent mineral collecting is a little more complicated. But folks are drawn to our hobby without even having learned how to collect white light rocks - the wondrous colors and glowing rocks draw folks like a moth to flame. This blog will attempt to guide folks new to the hobby who haven't had the benefit of collecting with experienced collectors in the selection of equipment, finding "glow spots and rocks", and ID'ing finds.
Your collecting style will probably determine the equipment and lights you will need - where and when will you be collecting? Fluorescent minerals are found almost anywhere there is a good selection of white light minerals. Mine dumps/tailing piles are obviously great candidates for any mineral, fluorescents included. Many abandoned mines and prospects offer good hunting, as well as remote areas with reports of an extensive assortment of minerals (such as Greenland). Unlike white light minerals, you will have to hunt for fluorescent minerals in the "dark" - either natural darkness or manmade. This means exploring at night, or carrying your own "darkness" with you.
Portable UV light - pretty much an absolute requirement. I know some people who can just about look at a rock and tell if it is fluorescent; not me. When I hike into an area to collect I want to be sure the rocks I carry out are good fluorescent specimens, so I always carry my light.
Flashlight - hunting at night? Rock piles, tailings, cliffs, forest trails - all very hard to navigate at night. Invest in a good headlamp (invaluable) and maybe even a white light flashlight.
Batteries - Your UV light needs power, lots of it. An average light is powered by 12vdc, and consumes 1 to 2 amps each hour. A 7 amp hour battery should last 3 to 6 hours. But keep an eye on weight; if you're hiking a long distance, up hills, etc. you might want to consider leaving the old lead-acid anchor at home and investing in a lightweight lithium battery pack.
Hammer and Chisel - odds are pretty good that you'll be scouring mine dumps that have been exposed to the weather for the last 100 years or more. The weathered exterior of a rock often reveals little about the fluorescence inside. You must be prepared to "crack that rock". Of course, any serious prospecting will require you to dig out veins, bust boulders, and apply serious strongarm methods - maybe even a sledgehammer will be useful. Some places might benefit from a prybar to dig rocks out of the pile/ground. I personally prefer a brick hammer that has a chisel side and a flat side, 4 to 6 lbs. Estwing makes some nice geological hammers - but pricey.
Goggles and Gloves - Hand-in-hand with the hammer to prevent rock chips taking out an eyeball. Plus - if you get the UV protection kind, they will double as eye protection when you get up close and personal with your UV light under a BBQ grill cover. A pair of good gloves would also be helpful.
Backpack - a good backpack will help you carry all this paraphernalia, and help lug your treasures back to the car.
Fluorescent Plastic Marking Tape - Called "Flagging Tape", great for marking areas you want to go back at night to explore. You've probably seen this kind of tape tied around trees in a nursery.
A couple of comments about safety are appropriate. Unlike ordinary rock collecting, fluorescent mineral collecting uses equipment which must be handled correctly, and we often find ourselves drawn to rocks which are uranyl activated. Both are subjects the first time collector should be aware of:
UV - Everyone knows that you should wear sunscreen at the beach; UV is harmful to the skin. Our mineral lights are extra powerful sources of UV. Common sense precautions should be used. Never look directly into a UV light with unprotected eyes, LW or SW. UV protection goggles are a really good idea. UV can reflect off rocks and bounce into your eyes causing "welder's burn" (flash burn). The result is usually a sandy feeling in the eyes - not fun. Learn more about the effects of UV on the skin and eyes in the GlowNotes post "The Photobiology of UV Damage to Skin". Most collectors rely on simple goggles for eye protection and, if their skin will be under UV for extended periods, perhaps gloves and long sleeves. Suntan lotion is another good protector.
Radioactivity - many of the green fluorescing rocks we collect are activated by the uranyl atom. Most are pretty harmless according to dosage charts illustrating microsieverts per day/year. For example, steenstrupine - a uranium crystal found in Greenland, is often less radioactive than your kitchen's granite countertop. For many years, "uranium glassware" was a popular dishware - we now collect it for the eerie green glow. But there are certainly some minerals that deserve our respect. Learn more about fluorescent minerals and radioactivity in the GlowNotes post "How Hot Are Your Rocks? Radioactivity in Uranyl-Activated Fluorescent Minerals".
The first expectation that newcomers have to the hobby is that they will be collecting at night. I have found that this often isn't the case. You will likely be exploring large piles of rocks, mine tailings, dumps, etc. - places you have not been to before. Many will be off-the-beaten-path, back in the woods, on the sides of mountains, edges of cliffs. These are not places to be wandering around at night, especially if you are not familiar with the topology.
I prefer visiting a locality when there is still daylight and perhaps, if safe, staying until darkness. That way I learn my way around in the daylight, and have a chance to look at the various minerals found in the area (in daylight). But more often than not I do my collecting in the daytime (or almost anytime in Greenland - land of the midnight sun). For this you need to bring your own darkness. The solution most folks opt for is a BBQ grill cover, medium size (custom fit for your size), and heavy enough to block the midday sun (thicker Weber covers work for me - just make sure it is fully opaque and doesn't have a white liner). Other options I have used include heavy duty plastic tarp (6 mil minimum), viewing boxes, or even a paint drop cloth. Whatever it is should be non-fluorescent and totally opaque (the sun is really bright, will shine through many cheap grill covers). Weight is an issue (that's why I like plastic) and keep in mind that a black grill cover doubles nicely as a sauna (bring plenty of water - you'll need it). (Hint: Don't forget to take off your sunglasses before diving under the grill cover!)
For some an ordinary longwave (LW) light might suffice (the Convoy 365nm flashlight is a great little light to carry everywhere you go). The problem with only a LW light is that you will miss many good fluorescent minerals. But the Convoy light is yielding some amazing results. It is so bright it can reveal fluorescence in minerals not previously known to be fluorescent under LW. For someone wanting to try out the hobby without investing the money for a SW light this might be a good choice.
A well-equipped FLM collector will carry a portable shortwave light (midwave really not necessary). A LW flashlight and a SW light will let you find just about any FLM; check it under MW when you get home - anything that glows under MW will also glow under LW or SW. Review the discussion about fluorescent mineral lights here to help you decide what kind of light you will be using. The brighter the better in my book, and I always worry about ruggedness and weight.
Where to find fluorescent minerals?
This is always the challenge. One of the best starting points is to join a club in your area and find out what collecting areas are around you. You may be the only serious fluorescent collector in the club but they'll at least be able to point out local mineral spots. Join the Fluorescent Mineral Group on Facebook - lots of folks from all over the world to help you with new collecting spots. Scour collecting web sites, trip reports, field trips, etc. Check Nature's Rainbows for minerals from your state (use the region's page).
Once you've identified a few spots do some research. Find the locality on Mindat.org and see if commonly fluorescent minerals are found from your proposed locality. Minerals such as calcite, fluorite, apatite, selenite, sphalerite, zircon, etc. all have a good chance of being fluorescent.
What kind of a mine was it? Scheelite, fluorite, or barite mines are hot contenders.
Are there dozens of minerals found at that locality? Odds are pretty good some of them will be fluorescent.
Uranium or REE mines are good prospects too.
The bottom line, fluorescent minerals are where you find them - they can be anywhere. Depending on where you live you may have to travel a bit, but it's worth the effort. You just have to light them up to find 'em! (But make sure you have permission to collect on private lands or restricted areas.)