Is it real or Memorex?

The fluorescent mineral hobby is a rewarding and interesting pastime.  Instead of collecting rocks that have no special abilities, no skills, or tricks "Glowhounds" expect their rocks to come with a special knack for surprising people.  Often they look plain old butt-ugly under ordinary lighting, but put them under an ultraviolet light and amazing things can happen; they glow, they change color, they even glow when the lights are turned off!  Sometimes they'll go so far as to glow different colors depending on what kind of light you use!

Collecting your own fluorescent minerals is (in my opinion) one of the most rewarding parts of this hobby.  But not all of us can travel to the special places where these rocks are found (Franklin NJ, Greenland, MSH Canada, the mines of AZ, etc).  We must thus rely on the "silver pick" to build a collection of world-wide fluorescents.  Ebay offers a wonderful selection of minerals from around the world, usually at very good prices.  But, unlike a geode bookend or an amethyst crystal, the pictures taken to sell these items are quite complicated and can be misleading if the buyer doesn't understand some of the intricacies involved in taking these photos.

UV Basics

To understand how fluorescent minerals are presented on Ebay you must first understand UV lighting.  Briefly, there are three basic types of UV lights:

• The most basic (and the one most people are familiar with) is longwave UV (sometimes referred to as "blacklight" - the purplish light used to make those old psychedelic posters glow).  Longwave UV lights (abbreviated LW) can be purchased as blacklights from many sellers on Ebay.  If you're a serious hobbiest you might opt for a filtered longwave UV light which emits UV-A.
• Shortwave UV (SW) is a very special light which requires a certain type of filter glass and emits UV-C (the kind used in room sterilizers).  This light can be harmful to your eyes, so do not look directly at it.  SW UV is the most widely used type of light in the hobby, as it causes intense reactions in most fluorescent minerals.
• Midwave UV (MW) is similar to SW UV requiring special lights, and emits light in between SW and LW.  It can cause many fluorescent minerals to glow a different color than either SW of LW.

Fluorescent Mineral Pictures

Assuming you have a good understanding of UV lights and the hobby, we can now delve into the world of UV photography.  Anyone who has a basic fluorescent collection will understand that our glowrocks "glow".  They react to the UV light and glow a different color (or several colors).  This glow is what makes our hobby so interesting, and makes it so hard to take pictures.  If you've ever tried to take a picture of a sunset you'll know what I mean.  The sun glows - and usually will overwhelm everything else in the picture (unless you're a skilled photographer).

Digital cameras are a major reason Ebay is such a great place to shop.  People anywhere can take pictures and post them for auction and you, the buyer, have a pretty good idea of what you're going to get.  Pictures of rocks are a little bit harder since it requires that the photographer pay attention to focus, F-stops, macro lenses, etc.  Usually to get a good picture of a small object the camera has to be real close - and many people just don't know how to focus a camera in close-up mode; thus the fuzzy pictures you see.

It gets even worse with fluorescent rocks.  Many (most) digital cameras are made for taking pictures of ordinary subjects (your kid's graduation, a day at the beach, the Grand Canyon) - not of things that glow saturated colors, in the dark, lit by a blue light.  Usually the camera just shrugs and makes these picture look like a fuzzy ball of blue spider webs, with bright orbs of color sprinkled around.  It takes certain settings to get things right, and if the photographer doesn't make those settings, you have to guess what the rock really looks like.  Your success in buying a fluorescent rock on Ebay will depend on how aware you are of the problems in fluorescent photography

Step by step - here are the things to watch for:

Focus - I believe there is not excuse for an out of focus image.  It's just not that hard to focus the camera.  But, if a seller has a rock which you want (based on the description) then you must simply rely on that (the description); better yet, bug the seller to take a decent photo!  If enough people do, he/she may get the hint.  If the picture is out of focus you can be pretty sure that the colors are not rendered correctly either.

Size - How big is the specimen?  Make sure that the seller states the size and weight, check to see if he has something to give scale to the rock (a hand, a coin, etc).  A photo that fills your computer screen can make a rock look huge, and you end up with a thumbnail!

Colors - This is the tricky part.  Very few people can take good fluorescent photos.  It takes years of experience, and a good camera.  Many items sold on Ebay have pictures where the colors are over saturated, the photo shows a blue cast, or some colors just don't show up.  A little understanding of this area and you might end up with a great deal on a rock that just doesn't look too great in the picture (or not be dissapointed when you get your 15 color specimen to find that it barely glows).

Blue Haze - be very careful with rocks that have blue fluorescence (hardystonite, fluorite, etc).  The UV light puts out a blue cast, and often these minerals will show more blue than they really have (digital cameras just love to enhance that blue light).  Worse, some rocks will show a blue FL where there just isn't any (most common with white areas on the rock that are not fluorescent - the white just reflects the blue back to the camera).

Burned out Color - Sometimes a photo will be taken with an extra long time exposure to bring out subtle colors, forsaking the integrity of the brighter colors (esperite, willemite, and calcite - the yellow esperite is so bright that it will turn white if the exposure is long enough to show the orange calcite brightly).

Inaccurate Colors - probably the biggest problem.  There are so many settings on the camera, types of lights, time exposures, etc that a picture can be taken such that it has no resemblance to the rock under study.  Only if the photographer is attentive and exacting will the picture be precise.  Add to this the tendency to use photo editing software (like photoshop) to correct color tones, adjust brightness levels, etc and you can end up with a picture that is just make believe. 

1. Compare the picture of the item to pictures in various books and magazines.  If the colors look unrealistic, they probably are.  Ask the seller.
2. Keep in mind that bright fluorescent minerals like willemite, esperite, tugtupite, and sodalite can be easily overexposed.  Reds can turn to yellow, yellow to white, green to white, and so on.
3. Be very skeptical of any blue fluorescence and make sure it is the mineral that is glowing, not just a reflection of blue light into the camera.
4. On multi-color specimens check the color of a known mineral (orange franklin calcite for example).  If that color doesn't look correct, odds are the color of the "what-is-it-ite" is probably wrong too.

Over Exposures - Keep in mind that even the dullest fluorescent mineral can be made to look like a glowing ember with a long time exposure.  For example, most feldspars glow a dull red but if you leave the camera shutter open long enough that feldspar pic will look like the brightest tugtupite around.  A good way (but not always true) is to look for surface detail on the image of the rock.  If the picture was overexposed most likely the detail on the rock will be gone - just a blob of whatever dominant color is being presented.

Examples:

Esperite and willemite:   This image is out of focus, and the colors are overexposed (and the wrong hue).  Esperite is a very bright, yellow FL mineral.  In this picture it has turned white, while the green willemite is probably at the right exposure but not the correct tint.  In this case you could do a search on the web (Google) for images of esperite, or compare to a photo in a book to get an idea of the proper colors.  The picture is not a good picture and does not do the rock justice; this might be an opportunity to get a nice rock at a cheap price (who would bid on such a sloppy pic?).

Tugtupite Combination Piece:  This is an example of an over-exposed picture.  The rock on the left is correct, while the rock on the right shows how colors can change and be exaggerated; reds start to turn yellow, greens turn white, and blue takes over the picture in general.  Be wary of pictures with too much blue, or solid saturated areas of color.  Look for large pictures with lots of detail to help you in your decision.

Rogerly Fluorite:  These two pictures are classic examples of how hard it is to take a picture of a blue rock - in this case Rogerly fluorite.  The picture on the left is out of focus, and the blue is simply too "burnt", while the picture on the right is focused a little better but the violet color is caused by the UV light, not the rock.  Focusing a camera in low-light situations is very difficult, and a blue rock makes it even more difficult.  This specimen is a simply beautiful fluorescent rock; again, try to find a good image somewhere to get an idea of what it should look like.  In this case (Rogerly fluorite) you can expect that this specimen will glow like all others - bright and beautiful.

Summary

I believe every fluorescent mineral dealer on Ebay is in it for the hobby.  Our hobby occupies a very unique niche and is a small community.  No one is out to mislead or cheat anyone.  If you have a question about a specimen ask the seller!  He/she will certainly be glad to answer your question, and will probably be very happy that you asked; it prevents misunderstandings and unhappy buyers.

Happy Glow Hunting....

MinerShop

Ebay Seller: www-minershop-com