New to the hobby? Check these posts out first for some basics on UV lights - https://www.naturesrainbows.com/fluorescent-mineral-lights

Rocks from the Franklin NJ mines? If you've seen the brightly colored fluorescent rocks from Franklin NJ, probably the most widely recognized fluorescent minerals, you'll need a SW UV light (shortwave 255nm). You also should consider a tube fluorescent mineral field light, as it covers a wider area compared to a SW flashlight (https://www.naturesrainbows.com/mineral-light-review-1).

Casual collecting - roadcuts, mine tailings, etc? Start out with LW, grow into SW. Get MW if you can afford it. A tube light also well advised for this style of collecting.

Longwave, shortwave, midwave flashlights are all the rage lately. 365nm, 255nm, 310nm - some amazing fluorescent minerals are being revealed using them. A very common question posted on our Facebook groups (Fluorescent Minerals and the Fluorescent Mineral Mart) are from new members asking which one is the best. To answer this question properly some other questions need to be answered first:

Fluorescent Sodalite? Many people new to the hobby have heard about fluorescent sodalite (aka "Yooperlites") found in the Great Lakes areas. Sodalite is usually brightly fluorescent under LW UV (longwave 365nm), and that's all you need - a good 365nm flashlight. But be forewarned, if the FLM hobby really bites, you'll soon be upgrading to a SW or MW light.

Once you determine your needs you can decide what's best for you. This blog post will list the current manufacturers of UV flashlights, along with links to info on tube based fluorescent mineral lights in case you decide that type of light is more suitable for your needs. No attempt is made to qualify the "best". But the list will only include lights I am very familiar with and come with great recommendations from the hobby community. I have not tested/evaluated them all but am intimately familiar with their designs. As always, Nature's Rainbows remains non-commercial and earns no money from these links/recommendations. This is an honest, unbiased list.

The colour of solids is due to various processes. There is no unique explanation for all types of solids. For solid metals, light interacts with the free electrons in the conduction bands. This results in a very strong reflexion for all the frequencies in the visible band. So, most metals have no special colour. You could call them white or grey but due to the strong reflexion they look shiny or "metallic". There are a few exceptions, like copper or gold. They have free electrons too, as all metals, so they are shiny. But there is some absorption of light in the green-blue band so the reflected light is displaced towards red. This absorption is not due to free electrons but to the electrons in the ionic cores, electrons on the "d" levels who can be excited to the "s" levels which for these few metals are not fully occupied.

Tube based fluorescent mineral lights are usually powered by an external battery pack. Larger and more cumbersome than a flashlight, but allows you to cover more area,

However, if you take a bunch of atoms, or molecules, and make a solid then some of the absorbed light will be converted to heat. The excited atoms are coupled to phonons of the material, so in this case the reemission doesn't happen.

Battery operated flashlights, self contained and very handy to carry. The LW types are high powered, excellent for hunting sodalite around the Great Lakes. SW flashlights are also high power but have a very tight spot, only lighting up a small area at a time.

Also, there are several blog posts about flashlights in the equipment section: https://www.naturesrainbows.com/photo-archive/categories/gnb-equipment

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I’m confused about why we don’t see absorbed light. The way I understand it is if an atom absorbs a photon then the electrons move up to an energy level corresponding to the energy of the photon. The electrons move down and emit a photon with the same energy so the emitted light would be of the same or lower wavelength as the absorbed light? When hydrogen is excited the colour seen is a mixture of the emitted wavelengths which are the same as the wavelengths absorbed. So why is it that objects that absorb red light reflect blue light? Is red light still emitted but we don’t see it, or does this energy absorbed completely disappear with no emission? Is emission of photons from excited atoms different to how colour is seen from other objects? I’d really appreciate if someone could explain this to me

Engenious Designs - https://www.engeniousdesigns.com/ SW, MW and LW flashlights as well as tube based lights. Based in the USA.

Visiting Greenland, Sweden, or other far off locales? If so, you're probably pretty serious about this hobby. I would bring all three wavelengths (SW, MW, and LW) and a tube based SW light.

For free atoms, you are correct. An atom will absorb on resonance light and reemit it after some time. This is resonance fluorescence.

For salts and other ionic compounds, the absorption can be due on either transitions between electron bands or on localized absorption centers like impurities or defects levels. For example, the colour of rubies is due to impurities. A pure crystal of aluminum oxide is colorless. With chromium impurities is ruby red.

John Dean - https://www.facebook.com/groups/2353537071585017 SW, MW, and LW flashlights. Only sells to members of his Facebook group, primarily focused on the Great Lakes areas.

Given the state of the art today, for field collecting I would probably go for a tube based SW light which can flood a larger area with light. If the Great Lakes sodalite were my specialty I would start with a 365nm LW flashlight.

China - Many sellers offer LW 365nm flashlights from China. Some are good, some are junk. All take forever to arrive, and ripoffs are rampant. Buy local for quality, buy China for price. You may get lucky. Good brands include Convoy, Wankedun, LightFE, Alonefire, etc. MUST have a filter to be useful.

This will be a big part of your decision. LW 365nm flashlights can be found for $15 to over $100 (useless 395nm lights can be found for under $10 - ignore them). SW and MW flashlights will run from $100 to $400, similar in cost to tube based lights. Anyone who has adopted this hobby as a serious part of their life owns a least one SW light and one LW light. MW lights will soon also be a necessary tool in your toolchest. And don't forget, a filtered light is a requirement - ignore those which do not have filters.

Silver pick? Browsing dealer inventories at shows for undiscovered wonders is one of my favorite pastimes if I can't get out in the field to collect. Here a flashlight is invaluable - all three wavelengths (SW, MW, LW).

Nature’s Rainbows is a non-commercial website for the hobby community.  It is maintained entirely by volunteer hobbyists and contributors.  Our mission is to provide information about UV and luminescence, premium fluorescent mineral photos, and a fluorescent mineral database for the enjoyment of FL mineral collectors around the world.  Information on this web site is covered under a Creative Commons License.