Update on Railroad Pass, Clark County, Nevada

My investigation of that area has somewhat stalled.

I was hoping that the fluorescent properties of alunite might guide me to that mineral on the hill. It is said to be extremely difficult to identify using physical or chemical means. Unfortunately, further research says its UV characteristics are uncertain.

The alunite examples I got from Minerals Unlimited are from  Marysvale  in Piute County, Utah. Mindat confirms that the mining district there indeed has alunite.

The host rock is richly pink, possibly from feldspar. The florescence the rocks show is confusing.

I read originally that alunite fluoresces orange under LW. Another website says it glows white under SW. Another authoritative site site says yellowish-white under both SW and LA. A hardcopy book I have says alunite is not normally a fluorescent mineral but when it does, it appears white to grayish.

The problem is that the specimens I receive glow softly green under SW and not at all under LW. Some of the rocks don’t light up at all. I have one rock from the hill that also lights up green under SW but it is much brighter than my reference samples and it has an afterglow. The ones from Utah do not.

Not all minerals are well researched for all the characteristics they may possess in all localities. For example, extremely few fluorescent mineral list mention that some benitoite glows red. But some small pieces do. UV may not be helpful after all but I have found a few other things lately in my self-quarantining.

I have Castor’s well respected Minerals of Nevada in my library. He says alunite is “abundant with pyrite at Railroad Pass.” Okay, as a gold prospector I certainly know what pyrite looks like. And two Nevada Bureau of Mines and Geology Examination reports mention quartz and alunite veins. Another mention of quartz. While I have found only one piece! Something is wrong.

In one of those examination reports are clear directions to another site on the hill, in the opposite direction of the area I was looking at. Armed with this information, I think I am now better positioned to find some well mineralized rocks. Just wished my back and leg were getting better.

I am now in physical therapy but and not making any progress, indeed, I having set backs. Still, I will probably make it back to the hill soon. Gold fever trumps all illnesses. Even when you are only looking for colors.

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Another Day For Railroad Pass and a UV Night Hunt

The best laid schemes o’ Mice an’ Men, Gang aft agley

I planned to get back to Railroad Pass today to sample drainages for colors. But I injured myself again and I can only walk slowly, carefully, and in pain. If I can get to my physical therapy appointment tomorrow I might some pointers on what to do. Aspirin certainly doesn’t help.

This delay might be good. Alunite specimens are in the mail for me and they might get here Saturday afternoon. I read they fluoresce orange under long wave. That would be tremendous since it would make night hunting on a difficult hill easier. The Convyoy C8 Dragonfly I have is a great hunting flashlight, much easier to operate than my bulky and heavy SW lamp. (Although that lamp from UV Systems is very bright, about 18 watts, totally reliable, and the battery lasts for hours.)

While the Dragonfly is great for hunting, its narrow and concentrated beam is too bright for bench or display work. It blows out colors on most materials. What might be a soft orange under a normal lamp will probably turn into a white spot at close range with the Convoy.

Again, while not a display lamp the Dragonfly might be the best LW hunting tool anywhere. I can hold it in one hand while holding onto a hiking stick with my other and it is almost bright enough to use as a pathway flashlight. It proved great on some steep hills at Darwin.  Have extra batteries and don’t run it continuously. You shouldn’t need to as a hill or other area can be scanned pretty quickly. And, yes, the battery charger for it is weird and funky.

If you do go out on a night fluorescent mineral hunt right now, make sure you are close to a populated area with emergency services nearby and be extra careful NOT to need them. Get yourself to help or self-treat. Most of us have a first aid kit, I’m thinking lately of getting a trauma kit. High risk activities should be curtailed until things get back to normal. Having an SAR crew pull you off a mountain during this pandemic is a criminal use of resources.

One last thing, since we are all concerned with cleanliness in these days of COVID-19. Many people use a “black light” to identify pet stains around the house or to help clean the bathroom. These are usually 5 watt SW units. If you REALLY want to see how disgusting your bathroom is and how much it needs cleaning, get a Dragonfly LW. You will be totally disgusted and in these times of self-quarantining , you will have a multiple-day project to spend a lot of your time. Everything biologic will present itself.


NB: All links are unsponsored and there are no ads at my sites. Midnight Minerals is a great company and so is UV Systems.

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The New Convoy C8 Dragonfly LW Ultraviolet Flashlight

Just got this handheld from Patrick Bigos at Midnight Minerals in Maine. I paid around $130 for my setup. That included an extra set of batteries and I also ordered a holster. The base unit is $85.00 but always order more batteries.

This Convoy is an amazing upgrade to my previous Convoy, a four year old S2+. That was a sad thing, underpowered, battery draining, finicky charger. But let’s not dwell on the past, technology has moved on.

This lamp produces recordable afterglow from even marginal rocks. With its concentrated beam it produces afterglow better than my 18 watt bench lamp.

This is just a first look. If you want to try night hunting for the first time or if you have some troublesome rocks to light up, give this Convoy a try. It is very impressive.

Here’s the URL”


Convoy C8 Dragonfly Long Wave UV Flashlight from Thomas Farley on Vimeo.

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Princess Pat Mine Afterglow

Afterglow demonstration from the Princess Pat Mine collecting area in San Bernardino County, California. This characteristic is extremely difficult to capture on video. In person the effect lasts for nearly a minute. I’ve run the video at half speed at a certain point to simulate what this looks like. The text announcing this point goes by quickly.

This is short wave under an 18 watt Way Too Cool Lamp. The mineral is willemite, the parent rock undetermined at this time.

November 12, 2022 update: If you look at this video on a big screen TV (Search YouTube for “Thomas Farley Channel” you’ll see the afterglow much better represented. I cut the video off during editing at the point my computer monitor showed no more glow. On a big screen, the glow still has a way to go. I will reshoot and you can then see the results on a TV.

Princess Pat Mine Afterglow from Thomas Farley on Vimeo.

November 13, 2022 update: Here’s the reshot video.

Princess Pat Mine Revised from Thomas Farley on Vimeo.

How long do you see afterglow continuing? On my unadjusted monitors, blackness comes in at twenty seconds, on my standard def TV blackness comes in at around 23 seconds.

I will be adjusting my monitors and possibly my TV to see if I can view the afterglow longer. This site has been recommend for adjusting displays:


That website is difficult to use. My iMac has a native calibration setup process that does not push the length.

In full screen mode using the original HD file, the last spot I see on my iMac is at 25 seconds. Even though I shot this in HD, 3840 x 2160, compression is going on at Vimeo where I uploaded it originally and then published it through Vimeo to YouTube. And I scaled it to 1920*1080 before uploading.


The Princess Pat Mine collecting site is described at this website by Justin Zzyzx who who has written Rockhound Barstow, the best and most current field guide to California’s Mojave.


This specimen was a kind gift from a friend.


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More From the Desert Floor

As a beginning florescent mineral collector I am excited about what I am finding, even if my discoveries are routine for the seasoned vet.

In a recent post I described how happy I was to find a rock with afterglow in an area not written about by collectors. Just last night, though, I discovered something else: one of my rocks fluoresces a different color in different wavelengths.

Normally, a rock or mineral will respond either well or poorly to a certain wavelength. Most materials reacting to shortwave will sit quietly under longwave.  And longwave materials respond weakly to shortwave.

What’s different with this chunky piece of field opal, or something like that, is that it changes colors under different wavelengths. The first photo is visible light, the second shortwave, the third longwave. Some calcite will change into a different color under all wavelengths, that including midwave.

I discovered this change accidentally last night as I was looking over my small group of rocks from my Sunday field trip. In the future I will be sure to check if any rock changes color, not just if it lights up. Multiple wavelength response is something collectors look for and something I will look for, too.

Visible light

Short wave

Long wave


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