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, 2019 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, 2019 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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My Best and Worst Find of The Day

November 12, 2019 Update: The Right People are on it! Cleanup scheduled soon.

Toxic waste dump in a culvert underneath the frontage road to 7 Magic Mountains and Jean, Nevada. I have reported it to Clark County and will follow up. I want to make sure this leaking, awful mess of used oil and possibly diesel waste is taken care of before it further contaminates the desert wash this culvert leads to.

Badly leaking oil mess.


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The Gold Lady in Golden Valley, Arizona

Located now in Golden Valley, The Gold Lady is a great prospecting and metal detecting store. The Gold Lady knows her stuff and she is an unstoppable when it comes to her own detecting; she is constantly in the field and mightily protests when health prevents her from going out.

The old store was fine but this new location promises good things. The Gold Lady has been advocating the Minelab Gold Monster 1000 for some time. Although I only saw it work at her old shop, its operation looks simple with a fairly flat learning curve. It looks like a great choice for the beginning prospector. Prospecting supplies and perhaps local maps.

The Gold Lady
52 Hope Road, Suite 2
Golden Valley, AZ 86413 (Northwest of Kingman)

35°13.168′ N 114°10.443′ W

Google Map link:

My last writeup:

The Gold Lady (internal link)

My travel list:


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Classifiers or Screens

Simple look at basic screens or classifiers. Uniform material makes for the best panning. Deciding how far down to screen depends on your patience and the size of the gold you are recovering. Probably small. I’ll try to put together a video that shows wet classifying, running coarse material down to fine.

In this video you’ll see regular screens and deep ones. Deep ones allow you to overfill a five gallon bucket just enough to work your material wet. They’re not meant to process more material, you really only want a screen a third full at the most when classifying.

Common Classifiers or Screens from Thomas Farley on Vimeo.


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Traveling Off-Road In The Southwest

Vehicle Tips

An Introduction

None of this post involves rock crawling. That is for well modified vehicles and their drivers who anticipate and plan for equipment and body damage. Think Moab or the Rubicon Trail. Also, perhaps confusingly, horsepower isn’t usually as important as gearing.

A Rockhounding Vehicle

Most rockhounds end up with a purpose-built four-wheel drive vehicle. They may start with a passenger car for rock shop trips or for paved roads to some collecting sites, but as the hobby takes hold they wind up with 4WD. Some drive crossovers and SUVs to remote off-pavement collecting sites but they risk their tires, their vehicles, and sometimes themselves. What follows is not a criticism of any vehicle a rockhound may have now, but a review of practicalities.

Four-wheel drive means differently applied power to all four wheels at the same time. Think about a vehicle making a complete circle or a turn on dry pavement. The inside wheels travel a shorter distance than the outside ones. 4WD vehicles adjust for this difference, operating all wheels with the correct power and play. Without this adjustment, a vehicle would stagger around the circle, perhaps leaving chunks of tire behind. That’s because all tires would be locked together, all turning the same rate over the different distance of the circle. Many vehicles, though, have locking differentials which force the wheels to turn together. They’re used when a vehicle threatens to bog under extremely loose or slippery conditions. More on lockers later.

What to Choose?

Every vehicle is a compromise. A stock jeep offers great maneuverability but carries fewer people and less gear than a full-size pickup. A pickup holds more gear but needs a tonneau cover, a tool box, or a camper shell to protect bed items. A camper shell in turn reduces visibility to the rear and sides. Work arounds are possible. Jeep accessories allow more gear by hanging items off the rear bumper or on top of the rig. A truck with a camper shell can have better side mirrors fitted to reduce blinds spots and a rearview camera to help with reversing.

A short wheelbase Jeep takes turns other vehicles can’t or with effort. Imagine a hard-left turn at the bottom of a steep hill. The Jeep may make that turn without backing up. A truck, on the other hand, may be forced to back up the hill to make the turn with another try. As mentioned before, larger trucks offer greater carrying capacity and a driver may wish to sacrifice some nimbleness for that virtue. Every vehicle is a compromise.

What Should a 4WD Vehicle Include?

Two-speed transfer case

All four wheel or all-wheel drive vehicles are not created equal. At a minimum, a rockhounding vehicle needs a two-speed transfer case providing what’s called high range four-wheel drive (4H) and low range four-wheel drive (4L). This drivetrain component operates off the vehicle’s transmission. The 4L setting increases torque or pulling power tremendously, keeping a vehicle going through thick mud or sand that would bog a rig operating in normal four-wheel drive or 4H.

Engage four-wheel drive only when needed, preferably, just before needed. That includes steep hills, snowy roads, deep sand, or mud. Anytime a road surface is loose or slippery. Which is often off pavement. Don’t underestimate the need for 4WD. A slight hill with wet grass defeats most 2WD vehicles. Engaging 4L means conditions have deteriorated substantially. Reduce speed to no more than fifteen to twenty-five miles an hour and let gearing do the work. A reminder. Ice defeats everything including 4WD. And some silt hills like those above Bakersfield, CA, will fill the treads of any tire, making even 4WD useless. Still, get a 4WD, exceptions or not.

Vehicles lacking a two-speed transfer case

Many crossovers and SUVs feature all-wheel drive (AWD) but lack a two-speed transfer case, the defining element of 4WD. The Honda Ridgeline, the Ford Escape, the Hyundai Tucson, the Subaru Forester and others send power to all four wheels but they cannot gear down the same way as 4WD.

Skid Plates

Skid plates cover some or all of a vehicle’s underbody. Especially important is a skid plate protecting the oil pan. These must be metal. Some vehicles have plastic plates underneath their frames for better air flow. These are not skid plates. Factory skid plates are better than none. Aftermarket companies like Hefty Fabworks manufacture 3/16” thick steel skid plates, which can armor a vehicle’s entire underbody. They are heavy, expensive, and require a lift to install. Most rockhounds can happily do with factory plates.

Tow Hooks

A vehicle needs frame mounted tow hook at front and back. These hooks permit a cable or tow strap to recover the vehicle once bogged. Without a hook there must be some other point on the frame to pull from. Consult the vehicle’s owner’s manual. A bumper or its facia will be torn off if used instead of a frame mounted hook. Lacking a tow hook at the back, a recovery point can be had using a D-ring shackle attached to a frame mounted hitch receiver. Never put a tow strap around a hitch ball. The ball may break loose and fly like a cannon ball into the window of the pulling vehicle. Never use chains. Never.

A Locking Differential (or two)

Many 4WD vehicles have a locking differential on the rear axle. Some have a locker on the front axle as well. As the name suggests, a locking differential forces both tires on an axle to move at the same speed. The lockers are engaged only when 4L no longer helps and the vehicle is at risk of getting bogged. Locked up, the vehicle will want to travel straight ahead, as there is no longer play between tires. Only the most treacherous, slippery conditions warrant engaging lockers and they must be disengaged as soon as firmer ground is reached.

Fire Extinguisher

Every vehicle needs a fire extinguisher fixed to a secure mounting bracket. Every vehicle.

Towing Package

A factory installed tow package is worth the cost, even with no towing is contemplated. A truck so fitted gets a greater capacity engine radiator and a larger transmission radiator. Possibly an oil radiator. The battery, suspension, alternator and charging system are all upgraded to handle towing’s greater demands. A truck with a tow package should run cooler under all conditions.


Batteries die quickly from heat and off-roading, expect no more than two years from a conventional battery.

Before going off-pavement with a conventional battery, make sure the battery top shows no undue discharge. Remove any discharge with diluted baking soda and a stiff brush.

Positive and negative cable terminals must be corrosion free and secure. If not, brush and clean the inside of a wire’s terminal lug and the post. A vehicle may not start simply due to corrosion buildup. Start by removing the negative terminal. Use a proper wrench and not a pliers. Once rounded over by a bad tool, the nut securing the lug will continue to break down when taken off again.

Go slowly if the lug resists removal. Pry if necessary but do not break the battery’s plastic top. Use a thin piece of wood on top of the battery to pry down on rather than the top of the battery itself. After cleaning the inside of the lug, clean or scrape the entire battery post. Make bright and shiny. Do not scrape so much that you distort the shape of the post, making the connection to the lug forever less certain.

Add distilled water to low battery cells. A turkey baster helps as well as a small flashlight.

Replace a battery cable if corrosion extends well into the wire, a job for a mechanic.

A battery must fit its battery tray exactly and be extremely secure. Check it. Never buy a battery that cannot be mounted correctly. A battery mustn’t thrash about the engine compartment.

Many off-roader’s favor spiral wound absorbed glass mat batteries or AGMs. Optima makes them as well as others. AGMS are made in a radically different way than a conventional battery. AGMs are sealed and require no maintenance. No filling, no leaking, no corrosion build-up. Upgrade to an AGM once an old battery fails.

Learn to jump start a vehicle and bring heavy duty jumper cables. Black goes to ground on the vehicle being jumped. Locate a good grounding point on the frame or find the vehicle’s approved connecting point. A vehicle won’t start without a solid connection for black.

Some vehicles go into an anti-theft mode when their battery dies, this may prevent jump starting without following a certain procedure. Check the owner’s manual. Replacing the battery or removing the cables will impact a vehicle’s electronics.

A spare battery or a handheld portable car jumper is mandatory when traveling solo. Or bring a lithium-ion smart battery like the kinds Goal Zero, Midland, or Suaoki produces. These can charge a dead battery as well as a rockhound’s electronics. Those smart batteries charge, not jump.

Automatic Transmission or Manual?

Most off-roaders favor manual shifting. Manual shifting offers better flexibility over changing conditions than an automatic. Stick shift vehicles get better mileage. It’s easier for recovery services to tow manual transmission vehicles. Automatics, though, are easier to drive. If a driver becomes incapacitated, it’s important that any person in the party can drive back to pavement. Every driver can manage an automatic. But many people don’t know how to drive a stick.

What is High Clearance?

Rock clubs will advise or require a high clearance vehicle on certain field trips. But what does high clearance mean?

A vehicle’s lowest point is usually measured at the rear differential or what off-roaders call the pumpkin. The distance from the bottom of the rear diff to the ground is the clearance. A base Jeep, the Wrangler Sport edition, has 8.4” of ground clearance. A Subaru Outback has 8.7” and a base Ford 150 has 8.8”. These are minimums for rockhounding vehicles.

Larger tires and a lift kit increase clearance and void any vehicle warranty unless modifications are factory approved. They pose other problems as well. Unless fording creeks, increasing a vehicle’s height with a lift kit or tires does little if the rear differential remains at or about the same height.

Tough Talk on Tires

The National Park Service, in discussing Death Valley driving, puts the problem well, “Flat tires are a common problem for backcountry visitors due to rough road conditions or from having unsuitable tires. Make sure your vehicle is equipped with ‘off-road’ tires rather than highway or street tires. Carry at least one inflated spare tire (preferably two), a can of fix-a-flat or tire plug kit, a 12-volt air-compressor, a lug wrench, and be sure all parts of your jack are on hand. Know how to use your equipment before you head out.”

The only useful off-road tires are light truck tires, designated on the sidewall as “LT.” These tires are much thicker than passenger tires and have stronger sidewall construction. Using obsolete but familiar terminology, a passenger tire may have four plies, an LT tire six to ten. It doesn’t matter what the rugged sounding name a tire may have, only the designation LT counts. Within the world of LT tires is a huge selection. But, first, recognize “P” tires and avoid them.

Mark of The Beast

Some new 4WD pickups come with passenger tires. Reject them when buying a vehicle or get credit for LT tires. Most Crossovers or SUVs cannot be fitted with LT tires. Reconsider the vehicle purchase. No vehicle with passenger tires should leave pavement unless driving well graded, rock-free roads. Subaru rally vehicles on TV do not represent how their passenger cars are built.

Any driver using passenger tires on sketchy roads should anticipate flats and have a plan to recover from them. Do not count on assistance, even on a club outing. Members coming a long distance for a special outing may be unwilling to cancel their day ahead by helping you out. Don’t blame them, blame you.

A donut spare or a temporary tire must be substituted for a full-size spare before going off-road. Many rockhounds carry two full size spares.

If a small leak is discovered, take the easiest approach to recovery first.

A can of Fix-a-Flat for large tires should be carried in any vehicle. Once Fix-a-Flat has been used, a decent size air compressor should fill the tire back to its normal operating pressure after a few miles of travel. (A compressor also helps with airing down and airing up tires in extremely sandy conditions.) In case of a flat, any rockhound with only one spare or those making a Fix-a-Flat repair must immediately return to pavement. Tire shops don’t like Fix-a-Flat but that is their problem.

Quick Note on Air Compressors

VIAIR and others make excellent air compressors for off-road use. Any compressor must run off the vehicle’s battery. Air compressors using a cigarette lighter adaptor are totally unacceptable. They are painfully slow and will burn out or overheat long before they can air up four off-road tires. Even when filling a single tire, small compressors will overheat and shut down, refusing to start again until cool.

Power must be drawn from the battery with the cables provided and the vehicle must be running the entire time of airing up. If not, the battery will drain immediately and die. The sliding hose couplers VIAIR uses demands great hand strength, look at other options if you have any disability. Or get a teenager in your group to connect the hoses for you. Expect to pay at least $200. Someone owning a quality air compressor and good LT tires won’t often need their expensive purchase. But someone in their group will. Count on it.

Back to Tires

Off-road tires and wheels are big and heavy. A complete tire and rim may be a yard wide and weigh 40 pounds. No rockhound should drive off-pavement by themselves without being able to change a tire on their own.

Sidewall flats are the worst. Tire dealers never fix a sidewall flat. Instead, they replace the entire tire. Tire repair kits exist for field repairs but not for sidewall flats. Repair as best as one can. Driving on a flat gets one further down the road but risks damage to the wheel. Driving on a flat is warranted, though, when getting a vehicle to a level spot for changing a tire.  Drive slow. Better to do this than attempt a tire change on badly uneven ground that might cause the vehicle to slide off a jack. And on to you.

Avoid hazards one controls. Keep from cactus, of course, but creosote branches broken at the right angle can puncture quality off-road tires. Stay fully on the route being driven. Avoid camping spots with fire rings where scrap wood may have been burned. Scrap wood leaves nails that are never picked up. A ten year old camp site like that will have nails everywhere. And stay on road in old mining districts, with hidden iron trash over every foot of ground.

Reduce speed. A rocky road at 15 MPH may not puncture tires but it may easily do so at 30 MPH. Some roads are so rocky the driver may not realize a flat has occurred for some time. Unfortunately, too many trip leaders drive too fast, leading group members racing to keep up with break downs resulting. Other than getting the leader to slow down, be prepared with a vehicle that can take an extra pounding from time to time.

AWD vehicles like Subarus have a special tire problem. All four tires must have equal tread wear or the AWD system will not work correctly or will break down. If a non-repairable flat is suffered when the vehicle is under warranty, it may be necessary to replace all four tires. If out of warranty, a used tire might be bought or a new tire shaved down to the right depth. Any of these steps means delaying or cancelling an adventure. Especially when broken down in a rural community without a tire store.

Many vehicles carry spares underneath their rigs, especially SUVs. A driver must know how to release them while on their back in mud or rain. A better solution is a swing-out carrier above the back bumper. Or a spare stowed inside the vehicle. This writer’s truck came with a spare mounted underneath. That is now the second spare. The first spare is carried in the truck bed, easily rolled out.

Take advice from a tire dealer familiar with off-roading. Develop a relation with this expert and their store. They will advise on tread depth and design, mileage expected, road noise, and a dozen other details.


–The Hi Lift Jack

The Hi Lift Jack is everywhere in the Jeep Community but of limited use for most vehicles. It’s mainly used to get a rig going that has high centered, one stuck on a rock or a ledge that puts a wheel or two off the ground. This jack utilizes lifting points close to the frame which most rigs do not have. It needs a base plate when in sand or mud. A Hi Lift can injure if used improperly. Before practicing, ask someone who knows the jack for one- on-one instructions. The Hi Lift isn’t meant for changing tires but if one does, chock the wheels and use jack stands.

–Off Highway Vehicle Jack

Pro Eagle sells off-pavement jacks that operate like conventional floor jacks. These are for high clearance vehicles, though not necessarily lifted. Check underbody height for compatibility before buying. These jacks may weigh fifty pounds. Despite weight, bulk, and cost, they make a good investment because they work in sand and can go under a vehicle to hit a variety of lifting points. There is a joy in using a jack that is dead simple, needs little instruction, and can be counted to work on every time. Again, chock at least one opposite wheel.

–The Bushranger X-Jack

Far lighter than any jack is this Bushranger product. It is a balloon like device that lifts a vehicle for chores like changing a tire. Jack stands must be placed before a spare is installed but that’s good practice with any repair. The X-Jack weighs less than twenty pounds and is inflated by the vehicle’s exhaust pipe or by the air compressor every rockhound must have in their rig. Many inexpensive copies exist. Avoid them.

Self-recovery Techniques

Solo drivers must have self-recovery plans. A long-handled shovel is mandatory as well as a tow strap should another vehicle come along. Maxtrax recovery boards are excellent. They permit a 4WD vehicle with off-road tires to get moving by first driving onto the boards, enabling momentum which is the key to getting unstuck. You’ll have to shovel first, however, when in sand or mud to place the boards. Recovery boards are far better than sticks or rocks shoved under a tire to give it traction.

A Last Note

A liberating force of a 4WD with heavy duty tires is to splash into pullouts one would never attempt with a passenger car. Every rockhound sees fascinating things on paved roads at 50 MPH, the question is, where can one pull over? Too many things are passed by because there is no where to turn out. After having a passenger car, it is a delight to bounce into pullouts that are within walking distance of a find. The world opens up as you confidently go off the road despite a drop a good drop in grade or surface. Try it.

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A Mystery Metal, The Whites’ GMT and the Falcon MD-20

Yesterday I went out to Lathrop Wells in Nye County looking for placer gold in featureless alluvium, possibly 240 deep where I was. I had the audio on my metal detector turned way down to save on battery life. I wasn’t listening for gold nuggets or gold in quartz that day, instead, I was reading the display on my Whites’ black sand tracker feature. It gives a numerical reading on any ground the coil is moving over. I sample when I see it go above 45, unfortunately, it only hit 42 once.

But one sandstone rock with black streaks blasted out despite the volume on the speaker being turned down. Well, I thought, that’s interesting. Aside from the possibility of gold, I wasn’t aware of any other metallic ore in this ocean of alluvium. No mining district here or any past mining activity. The signal sounded like the hot rocks I encountered everywhere in the the canyons of the forks of the American River. You get what sounds like a good signal and then you listen as the GMT cancels the signal out. I should explain.

A decent gold signal is a strong, low, mellow tone that happens each time the search coil passes over a rock. The signal remains no matter how many times the search coil goes over the target. What usually happens with a bad rock, often with an iron component, is that a signal is heard initially but that signal disappears after several passes. With each sweep the GMT is logging information to determine if a rock is ferrous or not. If so, the signal weakens and then goes away. This is called cancelling out. This rock did not cancel out. That’s what you look for with gold. Most non-metallic rocks are neutral and the GMT also passes them by without raising any signal.

The signal, however, was weak and wavy. Not good. You want to hear a steady signal, nice and low. You’ll rarely hear this. The Whites also has a probability of iron meter. It was reading at nearly 100%. Okay, I thought, this is coming home with me to figure out later. When I broke it open at home it revealed a dark material like that which it showed from the outside, hardness about three. Not attracted to a magnet, not even my super magnet. No U, no UV. Dull, off-white streak on a black streak plate. Metallic luster when freshly broken, annealed appearance in some spots with fresh breaks. Crushed and panned a piece, nothing unusual, no free gold at the macro or micro level.

To get the ID process going I mailed off a chip today by regular US mail to Kerry Day. He charges less than ten dollars for a seasoned opinion based his experience and the results produced by his electron scanning microscope and its supporting software.  I’ve written about his service many times before. I taped a small chip to my business card, put it in a normal envelope and the charge for mailing was less than $2.50.  Make sure your sample fits into a No 10 first class envelope, anything bigger might be considered a package and then mailing rates go up enormously.

My Falcon MD-20 handheld metal detector indicated that the material was non-ferrous, despite what my Whites said. Ferrous material produces a noise when an object goes away from the Falcon’s probe. Non-ferrous produces a signal as you move material toward the probe. This material only produced a signal going toward the probe, however, there are cases where a material is so strong that it may overwhelm the device and make it impossible to determine which is which. There were also some tiny gold colored spots arranged in lines here and there in the black material.  On seeing gold coloring, always assume mica or pyrite. The nice thing about the Falcon handheld and the GMT is they do not react to pyrite. Never. I have lumps of pure pyrite and both devices stay silent when moved over that nonsensical material. Pyrite is an iron associate but too weakly so. Yet the rock continued sounding off. I suspect that it was is not those gold colored specks making the noise but the black material.

Unable to resolve the difference between the two metal detectors, I gathered up the rock pieces and went back to my truck and the GMT.  I ran the coil over the rocks again. Sure enough, I hadn’t read the meter right in the field. This time the meter did not go above the halfway line, indicating something less than ferrous. The signal remained weak but still would not cancel out. Now, I just wanted to figure out what the material was, never mind that it wouldn’t be worth anything.

After further research I discovered that there are three long abandoned copper mines in the hills that drain to the wash I had been in. I still don’t know what that black material is but I am now convinced that I have a rock with copper. Not worth anything but a nice find. Those exploratory diggings are now unclaimed and the ground is on open BLM managed land. A little close to the Nevada Test Site boundary but at least a mile away. I may go exploring there to look for copper mineral specimens. Here’s a link to one mine listed at the the MRDS if you want to go:

Lucky Claim:

Materials Type of material
Malachite Ore
Hematite Gangue

Fractured quartzsite with slight banding

Lathrop Wells Collecting from Thomas Farley on Vimeo.

Tuff, Explosion Tuff, and a Cat

Got to get out the door quick to hound some more ground. A few words here on tuff since I am investigating a tuff formation outside of Las Vegas. See previous posts.

Tuff are rocks formed from solidified or lithified volcanic ash and rock fragments thrown out of a vent. They can be all colors and densities but a common feature are clasts, rock fragments within the tuff. Not all tuff contains clasts but this is very common.

UPDATE: November 11, 2019. Made a better video than the previous. Retains cat content.

Volcanic Tuff and Cat from Thomas Farley on Vimeo.

Most of my tuff reference specimens come from here:

I might have found an example of explosion tuff. This is where rocks settled onto the ash, rather than being embedded in it. Need to collect more of that, break some of it open, look for other things while I am out in the field, and on and on. . .

Another look at this possible explosion tuff and a still photo of what I am calling “The Shark”. A single, angular clast sticking out of tuff from the same area. Looks like basalt to me. Is this explosion tuff?

Explosion Tuff? from Thomas Farley on Vimeo.

The Shark


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Mystery Crystals Revealed as a Mystery


The results are in on those small crystals I found in tuff near Jean, Nevada. Kerry Day says they are a mystery mineral, possibly orthoclase. That’s a feldspar member, a group of rock building minerals. Although the geologic map for the area lists sanidine as being present, geologists aren’t all skilled mineralogists and sometimes small mistakes occur. Sanidine is another feldspar mineral, closely related to orthoclase.

Feldspar imparts a pink color to many granitic rocks. Feldspar minerals aren’t much collected unless they display good crystal form or come from a rare area. Like the anorthoclase found at the Mt. Erebus Volcano in Antartica. says orthoclase is “a alkali feldspar intermediate between low sanidine and high albite.” Hmm. I’ll have to read up on that but in the meantime have asked Wendi at Minerals Unlimited to send me specimens of those two. I’ll put them under my microscope to compare them to what I have. Positively identifying any of these minerals by sight,  however, is really impossible. has an excellent article on anorthoclase which says that distinguishing between albite, sanidine, orthoclase, and microcline requires x- ray analysis, probably X-ray diffraction. The usual visual and physical tools for identification: determining luster, hardness, cleavage or fracture, and so on, don’t matter much when minerals are quite alike. Rather, something like the percentage of potassium in a specimen may make the difference.. And you’re not going to determine that with with a field guide or anything else online. Test.

This is a labeled spectra of the crystal sample I sent Kerry Day. His conclusion:

“Mystery mineral = Not Sanidine, insufficient K. Probably Anorthoclase. (Now orthoclase, ed.) The spectrum does not fit Chabazite.”

With that comes his qualifications:

“That spectrum was created with a Cambridge S100 SEM, a XR-100-CR pin diode detector and DTSA software. X-ray counts are on the vertical axis and X-ray voltage is on the horizontal axis. For various reasons peak heights are not directly comparable.

The accelerating voltage was 25 KeV. This setting exaggerates the higher voltage peaks. Detector efficiency peaks at Ca, thus, all Ca peaks are greatly exaggerated. NA IS VERY POORLY DETECTED BY MY HARDWARE. [NA is sodium, ed. note]

Some elements create more than one peak. All elements have been labeled.

My X-ray detector cannot detect Li, Be, B, C, O, N or F. [the lighter elements, ed. note]

Uncoated specimens charge up under the beam and generate false peaks such as Al (1.49), Si (1.74), Cl (2.61) and Ni (7.47). These elements are coming from the inside of my SEM chamber. Surrounding minerals also contribute. Any element I believe to be extraneous I did not label.”

So, what do we have?

One Method For Further Testing

Calculating a mineral’s identity by its geochemical composition is a good step when the usual ID methods fail. Kerry Day uses a method called qualitative EDS analysis. A qualitative test differs from a quantitative test in that it may be less precise but it is far, far less expensive. Quantitative testing is usually only needed when publishing results in the sciences or when working in an industry with critical concerns. NASA needs quantitative, you probably don’t.

Kerry Day uses his own Scanning Electron Microscope or SEM to perform mineral identification. He writes, “When high energy electrons from a scanning Electron Microscope (SEM) bombard a mineral grain, they generate X-rays of voltages specific to the atoms being bombarded. An Energy Dispersive Spectrometer (EDS) then detects these X-rays and displays them in graph form on a computer. Interpretation of the raw graph is called Qualitative EDS analysis.”

An element-based formula can express a mineral’s chemical makeup. Like this for turquoise:

CuAl₆(PO₄)₄(OH)₈ • 4H₂O

Cu is copper, Al is aluminum, PO4 is phosphate, OH is hydroxide, and H2O is water. The subscript values indicate their proportions.

Day considers the elements reported in a sample. Relying on years of experience, he then tries to match these elements to a mineral formula. His equipment does not test for every element nor do other kinds of analytical tests but the major elements present are often enough to identify a mineral in this manner.

Day charges $8.00 for each spectrum conducted, with the peaks of the spectra indicating which element is present and the height of the peak roughly approximating its proportional abundance. His report generates a labeled-spectra which is e-mailed and which you can see above. Kerry says, “A sand-sized grain or a scraping in a gelatin capsule or taped to paper is sufficient for the this analysis.”

You might pay more for postage than the test itself if you send your material as a package. Fit your sample instead into a No. 10 envelope. The USPS should charge less than $2.50 for a first class envelope to Canada. Although Day accepts cash tucked into a sample’s envelope, you can pay for testing through his Etsy store. That will prevent customs or your shipping company from delaying your sample should they have a problem transporting money.

His website:

His Etsy store, under the name KGDOLMC, is here:

His selection of minerals and rocks, by the way, is wonderful. Inquire if you don’t see something you are searching for. I have bought many things from him. Back to testing.

This testing is primarily for minerals, not elements. For example, an EDS analysis of colored chips from a petrified wood sample will probably reveal the mineral quartz, the host mineral, and not the trace elements coloring the chips. In the case of pet wood, Bob Jones says these colors could come from vanadium, chromium, manganese, iron, cobalt, and many more. Any of the so-called transition metals. Again, these are elements, not minerals and Day’s equipment may not pick them up. An EDS analysis may disappoint when a minerals are expected and instead undetectable trace elements produce an inconclusive report.

If known, you might include in your correspondence with Day the minerals documented to exist in your collecting area. might provide this for a well noted area or perhaps a list might be had from the applicable geologic quad.

What Now With My Mystery Crystals?

I’m wrapping up my efforts with the samples I collected. I’ve noted their location in a Word doc and have included portions of the Jean Quad, the geologic map of the area. Along with the test results Kerry Day provided. It’s not everyday that you find crystals that come in squares, rectangles, and sometime arrowhead shapes. It’s been fun. My mineral friend Rolph in St. David Arizona, says orthoclase is common there and brings about a sparkling character to many areas.

I’ll now store away my samples with this paperwork and go on to finding other things. Perhaps I’ll make this file available online in case the one or two feldspar specialists in the world ever decide they want to look up this occurrence. Maybe some student twenty years from now working on their Masters’ thesis. It could happen! 🙂


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Unexpected Geode Find!

Returned to my collecting area with a rock that showed interesting character but little lime/green under SW UV. Best to break it open to see if any more UV would be revealed. While I hoped for decent response, I was not expecting this rhyolite to be a geode.

Last year I collected a similar looking rock from the Armagosa Valley in Nye County, Nevada. Bryan Smalley cut it open and it was just a sad looking mix of brown rhyolite and quartz. This is now my first self-collected geode. I normally would not hunt them since I have no idea where they might be.

I am still looking for uranium occurrences and have had yet to find any. I may, though, have identified sanidine crystals in tuff so that is a good thing. I’ll be back.

Breaking it Open In The Field

Unexpected Geode Find! from Thomas Farley on Vimeo.


Under SW UV, Along With My First Brachiopod (Shell)

Unexpected Geode Find Under Shortwave UV from Thomas Farley on Vimeo.


I also found my first brachiopod! Photo below:


I may have also discovered a concretion naturally split apart. See below.

Concretions are typically sandstone based. Those might form around a piece of a shell (limestone in nature) or a bit of calcite. My rock fizzes hardly at all, which makes me think it is not sedimentary. Bates and Jackson say concretions can also form around a leaf, bone or fossil and that concretions can derive from “fragmental volcanic rocks.” I’m still reading up on this.

Picture below is my rock and a reference sample I have from Geological Specimen Supply. That rock comes from the Tule Wash in Imperial, County, California.


35.830022, -115.285060

Jean Quad


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Version 9 of the Southwest Travel List is Out!

My latest list of Places to Visit and Collect in the Southwest is the best ever.  This post may say Version 9 but I have since done Revision 10.

Or get it here:

Version 10, November 6,  2019

This page always has the latest version of my Places to Visit and Collect in the Southwest. (And beyond!)

.pdf (Printing and desktop work)

Version 10 , November 6, 2019





.mobi (Kindle format for mobile devices):

Version 10, November 6, 2019 

SW Places To Visit Or Collect 10 – Tom Farley




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