The season of Scorpio often brings good luck to me in the Colorado Rockies, and this year I was treated with a special find (large quartz crystals)! As most rock hounds probably experience, as you gain experience you think of old places you’ve dug and the potential for those spots still producing crystals now that you know what you didn’t during the original dig.
This otherwise drab (likely microcline) rock was coated with secondary crystal points. Really interesting growth pattern too.
There was a spot I found many years ago where I found a couple of floater crystals that were so-so and I abandoned that dig site prospecting for lusher areas. I have always wondered, what if I dug deeper in that spot? I didn’t think I dug deep enough but I always wondered if it would be worth the effort to try that area again as it was a bit of a hike with several steep hills. So I have been thinking about this spot now and again over the years and I finally decided to prospect that area again.
In early November I went out on a crisp morning and found myself in the area of this dig. I wasn’t having any luck prospecting, so I decided what the hell, I need to resolve this once and for all, so I hiked back to that spot. I reclaim all my digs and after many years away they have grown back the ground cover and looked good, which was pleasing. I ended up digging in the area that I had long thought about, and within about 30 minutes starting hitting some signs.
The area had some large rocks and as I dug around them I started to see some darker coloration, which ended up being pegmatite. Digging into that started to produce some flats and faces and it wasn’t long before the first crystal popped out, maybe a foot underground and in a peg seam. After the initial crystal I started to see the seam open up and then experienced some harder clay. Only once have I hit a really thick clay, but I could tell right away that experience was happening again.
This plate came out in 3 pieces which is repaired above. The main part of the plate was at the top of the pocket, as seen in the video. The left crystal had sunk to the bottom of the pocket after it was shattered off, you can see me pull it out in the video immediately before I pulled out the larger healed crystal toward the end. The upper right piece was also at the bottom of the pocket. It pays to save all pieces and parts.
Working in the clay requires metal tools, there is no way you can get it out with your fingers or even wooden material. I have a dulled screwdriver just for these times. I started to pull out quartz crystals but they were all heavily overgrown with a brownish, sharp milky quartz-type crystal. It wasn’t coming off, that’s for sure, and I thought perhaps it would require a little soaking o loosen up the overcoating. So I continued to dig and starting pulling out some really nice crystals, but it was VERY slow going and somewhat tedious on the fingers and wrists due to the clay.
As I continued to dive down with the pocket, the clay got thicker and the crystals got bigger! It finally ended up where there were many large crystals all at the bottom of the pocket. I could tell the pocket collapsed because I found bits and pieces of broken crystals in between these larger ones that matched up to crystal parts I was finding at the top of the pocket.
The crystals all have several stages of growth. Most are coated with a brownish quartz like coating. I could tell there was microcline in the pocket, but it appears to have all been corroded away and the replaced on all the smokey quartz throughout the pocket. Must have been some acidic stuff in the pocket during its creation!
This crystal is typical of almost all crystals in this pocket. Multiple layers of additional growth on the original smokey quartz. It is very difficult to remove–this has been soaking in SIO baths for a while, and a water gun does nothing. I will attempt mechanical means as soon as I get that available to me. But the crystal is GEMMY inside!
Needless to say, these crystals are going to be VERY difficult to clean. Super Iron Out has pulled some of the coating off; leaving behind a harder, sharp layer of quartz type coating. I was able to shine a light through the side of a quartz, and the big crystals I found are all typically very gemmy inside–at least those I could peer into. So I am looking into an abrasive solution to help make some of these large, beautiful smokey quartz crystals shine!
This was one of the largest pockets I have found, definitely the largest by far this year.
If you have any tips to help me clean these, I’d love to hear your suggestions. Note that I put a couple of crap crystals in a beaker of fully concentrated muriatic acid and it did clear the brown off, the quartz-like coating did not get touched.
This was on a very small piece that I am not sure why I brought home…typically if in question it comes home to get a rinse. It was covered with tiny crystals as seen in this macro shot!
Crystal digging time has been limited this summer, however I was able to make it out several times this fall having several successful days! This day in late September I was able to find a fun smokey quartz and light amazonite pocket. There was an antler my dog found that he enjoyed all day long; the cool part is where he found it! Investigating the area he led me to showed some promising signs on the surface. I dug a few test holes and eventually found a crystal pocket! I feel it thus is appropriate that I named the pocket after him (his name is Boogie)!
Boogie chawing on a an antler near my test hole, which ended up in a couple small pockets
At the point of the antler, there was a few quartz and feldspar chunks laying on the ground. Digging a test hole there, I found a couple of pieces of float pegmatite within the first 5 inches so I followed the float peg up the hill. Its always a good sign when you can follow a path of float rocks up a hill, especially if there are euhedral sides, which in this case there were not any flats. A short while (maybe 5 feet) later uphill the peg stopped showing up at the float level. Often this sudden stoppage of float material means that whatever was producing the float is back downhill.
Going back down the hill a few feet, I dug deeper and found more peg! Following that led me to the host peg which started maybe 8 inches below the surface. It looks like I found the source!!! Now, hopefully the peg chunks will start having flat faces and become more crystallized ending in a seam or a pocket!
In this hole, digging down, I was able to hit the bottom of the peg seam where it turned into crumbles of granite gravel. Going up hill I ended back into gravel, so I feel I found the girth of this pegmatite seam. That said, nothing interesting was presenting itself, yet…
Next, I followed the peg from side-to-side. Within about 30 minutes I found a few nice terminated quartz crystals and a few smaller pieces. This is documented in the first few minutes in the video, below. The quartz ended as soon as it started, however, and I ended up on a fruitless dig in that direction for about an hour longer…that is typical of me, when I find crystals I go in that direction for an extra long time just to be sure; someday I’ll figure out when to stop earlier…or not.
Next step was to take a break and eat lunch. After looking at what I had dug and the size of the pegmatite from different perspectives I figured there was only one choice, to stay on this peg which had produced quartz crystals and dig the other way. Soon after digging that way I was pulling out some quartz and microcline with sides, and finally some microcline crystals. This is where the video continues.
The pocket contained a lot of chunks of microcline/light blue amazonite but none were fully euhedral, until the very end which contains a big 5″ crystal in three pieces. Many of the crystals were good size and had many faces. All were heavily coated in iron oxide. I did find some quartz too, especially in the center and lower parts of the pocket. The quartz had interesting staining, all having a secondary coating of grey/white quartz on their tips, and then on 3 of the faces horizontal lines of the same secondary coating while on the other three faces heavily iron oxide stained. They all had similar coatings and stain patterns which I found interesting!
The find of the day was a smokey quartz and cleavelandite combo, a 4-5 inch smokey quartz with excellent patterns in the secondary coatings and staining, and a 5″ wide light amazonite crystal at the bottom of the pocket.
Cleavelandite and Smokey Quartz combo with mica sprinkled around it. The quartz has a secondary coating of quartz.
Almost all the quartz had a secondary coating of milky quartz on top and the amazonites and microclines were heavily coated with iron oxide. There was a very large 5″ amazonite at the bottom of the pocket which was in three pieces, but they fit back together nicely. All have been in the cleaning bath for a while and have yet to clean up to my liking, except a few in which the staining adds to the color and character! I’m working on abrasive methods and hopefully will have cleaner pictures to show soon.
Large amazonite (light blue) found at the bottom of the pocket in 3 pieces. Undergoing a lengthy super iron out bath.
Light amazonite with mica still heavily stained after many weeks in a SIO bath. From the video.
Cool pair of smokey quartz showing the parallel growth and quartz caps
A couple of the smokey quartz showing the overgrowth of quartz on the points.
Largest smokey quartz from the pocket. I’m done cleaning it as I really like the lines and their parallelism to the crystal faces. This is shown in the video.
As I’m experimenting with my new Macro lens and crystal photography. I am trying to figure out how to better shoot crystals using a macro lens, which I am really enjoying!
I have been cleaning some crystals in an Iron Out bath recently and thought I’d take some progress shots. These are crystals dug earlier this year and some last year. Here are some of the experiments.
These two both came out of the same area of the little seam I was in. Both had interesting secondary growth patterns! f11,1/100, iso400, 90mm
This one had small crystals growing in the overgrowth gap. Interesting etching as well. Needing a good depth of field for these macro shots. Manual focus, f11, 1/100, iso1250, 90mm.
This crystal has some interesting faces in the overgrowth. Trying to capture the point and the faces in focus, so needing a deep depth of field. f11, 1/00, iso1000, 90mm.
Amazonite. f11, 1/100, iso125, 90mm
This crystal has some neat little gemmy sidecars. f11, 1/100, iso1250, 90mm.
I love this side shot showing the color zoning in the crystal. Love the sawtooths at the top left! f20, 1/100, is0640, 90mm.
Side view of 1/2 of this crystal.
Was going for a shallow depth of field for this end crystal which shows the iron staining and multicolors this fluorite has to offer! f5.6, 1/100, iso100, 90mm
This is part of a much bigger fluorite crystal that disintegrated once I tried extracting it. But the apple green contrasting with violet is amazing! Background was the 12 inches of spring snow and the crystal was backlit by the morning sun. f3.2, 1/2000, iso100, -0.7 step, 90mm.
This is two of the three pieces I was able to salvage. They are still pretty stained with iron oxide, will continue giving a iron out bath. f9, 1/100, iso100, -.7step (oops), 90mm.
Last year I published an article How to Find Crystals that detailed some of the techniques I use and general prospecting tips, hoping to give several tips and hints to aid in expediting the learning curve of digging crystals. I’ve gotten some great feedback from that article and appreciate all the comments.
One of the things I tried to cover in that blog posting was what to look for on the surface and how to know if you are in a good spot and should continue digging, or bury the hole and continue the prospecting elsewhere. I knew it would be difficult to share that experience, as I’m still learning myself and it’s one of those things you can read about all day long but you don’t “get it” until you actually can see and experience how it is done. The pictures and text in that article were helpful I feel; but it still left me with questions after reading it–knowing that I had a plan for this year’s prospecting trips…
That blog posting was just the first of many postings I plan to do sharing what I’ve figured out on finding pegmatite crystals. I was able to get out digging late this spring and my goal was to take some video while I was on the hunt, hopefully showing what I look for on the surface and what I look for as I follow the pegmatite trail to the crystals (assuming I find crystals, which many times I don’t)! This video hopefully will provide some tips and hints of what works for me in the toughest part of the process, the initial prospecting and test holes.
Unfortunately due to leaving the camera in the sun too long, the pocket extraction video was corrupt, but the good stuff from a prospecting perspective was saved showing progress as I was hunting for the pocket. You’ll see that demonstrated in the video below.
I would love your feedback, questions and suggestions. I plan to do other videos showing different techniques.
The small crystal pocket I eventually hit I’m calling the OneTwo. It was mainly Microcline crystals, most were Carlsbad twinned! On these, once cleaned up, opposite faces had a blue tint of Amazonite to them; not as deep of green color as you find elsewhere in the region, but still really nice and a lot of fun. The smokey quartz I found all had secondary coatings of a darker colored quartz which will be very difficult to remove.
Interesting cluster of Amazonite / Microcline joined at a ~45 degree angle.
Carlsbad twinned Amazonite (light blue) with a small amount of cleavelandite sprays.
Nice little pair of Carlsbad twinned Amazonite with a bit of cleavelandite.
These are the largest crystals from the pocket, each about 3.5 inches tall. They had to be repaired as they came out in 3 pieces, the cap to the larger crystal was cleaved off and the two crystals had been separated and were found about a foot from each other in the pocket.
Smoky Quartz showing the secondary quartz growth. These have been soaked in a heated chemical bath for several weeks and look at lot better than they originally did; but this is as far as I will clean them as the quartz underneath is not worth the effort.
Some of the nicer twinned amazonites from the OneTwo pocket.
Examples of the coated smoky quartz from the OneTwo. The larger crystals are nearly 3 inches long. There were mostly microcline crystals in the pocket; which is opposite of what I typically find in the region.
Recently I dug some phosphorescent fluorite crystals, I don’t have a good UV source except for a cheapo LED lamp I bought from China, but I decided to give this a try. There was enough UV that some of the crystals did phosphoresce a blue/greenish color. I’ve never checked out any of my crystals this way so it was awesome to see the illumination continue for well over a minute. I wonder what a more powerful lamp would do?
I am still experimenting with what quality of the stones allows the phosphorescence. At first I thought that only the more gemmy of the crystals I found phosphoresce, but that isn’t true. Some of the most gemmy crystals do not phosphoresce at all!
Here is an example of a clear gemmy piece of Fluorite I found, it is pretty but does not phosphoresce.
Here are the fluorites phosphorescing. I charged them up with a cheapo UV LED lamp, then turned off the lamp and opened the exposure for 5 seconds in the pitch dark. They were a bit more green than this picture shows. They stayed illuminated for several minutes.
Was able to pull off some winter prospecting this month! Typically rockin’ season doesn’t start here in the Colorado Rockies until April timeframe, sometimes a bit later when the snow is all melted and the ground good and thawed. But this winter is a little different and I have been out prospecting several times since early February already! Yes, there is snow to contend with, but not enough to keep me indoors!
I was able to hit three different spots so far this winter. All three spots had snow, but there was enough good southern exposed area to have limited snow and somewhat thawed ground.
The first prospecting trip I found signs of quartz and feldspar leading up a hill and followed it. In several cases I found signs of other digging; good news is I was on the right trail; bad news I was on it after others were…but the signs were good and I suspect there are other areas to check out, so chalk this area up to needing another trip!
The second place I started finding some float about 6 inches under the surface. Heading uphill I was able to find several cool crystals (and many more quartz with faces) so I feel confident they did float downhill; but I haven’t found the source yet. Either the original pocket was above present day ground, or there is more searching to do. I’m trusting the latter will yield results and plan to hit this spot again this spring.
interesting quartz crystal coated with hematite giving a very sparkly luster to the stone.
Large five inch smoky quartz float crystal. This one had a fracture and rehealed; must have busted during formation a billion years ago!
This crystal is awesome, the best one I found. It is double-terminated with several coatings, one of white quartz and the other of hematite.
Same crystal as above showing the double terminations and multiple growths.
The third area was one I have visited before, before long I was back into the pocket mud which was very sticky and messy! I found some neat fluorite crystals and some rather odd and interesting quartz. None of these have been properly cleaned but will show you the parallel growth and unique crystal clusters.
I love the larger quartz crystals around the edge, and the elestial growth in the center!
This quartz cluster were terminated everywhere (thousands of times), and differently terminated on both sides. Probably my favorite find of the day! This side has white quartz in parallel elestial growth patterns.
This side had the one larger quartz crystal with the smaller points adjoining it. Can’t see it much here, but it has a tint of green throughout!
I love this fluorite, fairly gemmy and has some purple, otherwise clear. As you gaze into it, it sucks time from existence!
Several pyramid fluorites came out of the this spot. This is the smallest, and gemmiest…I immediately came up with this idea for a photograph, so I carefully wrapped this in newspaper and to my delight it was clear enough to pull off this shot! Fun!
Got my itch to do some prospecting early this spring which was fun! Look forward to heading up again here soon, hopefully! Spring has not yet arrived!
I often get asked “How do you find crystals you have posted?”. Which techniques to use is a very subjective question, but certainly there are standard ways of prospecting for pegmatite crystals here in Colorado. I will try to cover some of the techniques I use in this blog post.
UPDATE: I have posted another blog post showing examples of these techniques here.
It has taken me years of prospecting, tons of reading, and networking with other prospectors and rock clubs to figure out what I’ve learned to find crystals so far, so I’m hoping that if you are new to this hobby this article can help expedite the learning curve and take away some frustration…i.e. not coming home empty handed as often! Note that I sometimes STILL come home with nothing to show (and I keep even the littlest crystals)…I think of it like fishing, sometimes the fish simply aren’t biting. My other hope is that folks having successful techniques can share their wisdom so I and others can continue to learn (the comments on this article is a great place, hint hint !!!). Note I am self-taught and have no formal geology schooling or experience, so my descriptions in this article may be scientifically inaccurate; the goal of this article is not to explain the science as much as for tips to helping you learn to find crystals! Of course the science is helpful and very interesting, if you have anything to share or correct (or have further questions), please leave comments, I would love to hear your techniques, opinions and knowledge on the subject!
Hitting a crystal pocket gives you a tremendous high! This was my first crystal pocket!
How to Find Crystals
There are three standard ways I prospect when searching for crystals; I may use only one way on any given day, or may use all three:
Searching the tailing piles of other digs
Finding float and following it
Digging in the source pegmatite
Prospecting Tailing Piles
When I’m prospecting I always check out old and new digs. There are several reasons for this–to learn what the other prospector was into when (presumably) they find crystals themselves, to perhaps continue where the previous prospector didn’t go, and to search through their tailings to ensure the weather didn’t reveal something that was missed or discarded!
Mount Antero double terminated Phenakite my son found laying on the surface, would have been great to have more of that aquamarine attached!
If the prospector was into a pocket or seam of crystals, they may have had mud or iron coatings on the crystals so the prospector tossed aside because they couldn’t see the sides or simply missed it…it happens, I’ve gone back to my digs before and found incredible crystals that I somehow missed! After a good rain or season of snow Mother Nature may help to reveal crystals that were left behind! This is the easiest form of prospecting. I also find that some prospectors are not interested in “boring” or imperfect crystals; another person’s trash may be my treasure! I have found many great crystals by searching the tailings of previous digs!
to find crystals it helps moving around the pile to get a reflection of sunlight from a flat shiny surface of a crystal…you should train your eyes to focus on any flat sided rock
getting down closer to the ground for a different perspective; I find many crystals this way that I missed standing up
look for color, some crystals are coated with iron-based minerals and may look rusty
poking around the sides of the hole to see if the prior prospector left part of the pocket
looking for float from the pocket (talked about further below)
dig through the tailings to see if other crystals are slightly buried
Finally there is a lot to learn from studying what others were into. This is how I’ve done much of my learning. What did the rocks they were pulling out look like (note to self, keep an eye out for these signs in my holes)? Are there other digs along the hillside along the same “zone” that I should also check out? What did the other person see that kept them digging? The bigger the prospector’s hole the more likely they found something good (otherwise that is a lot of effort for nothing), so explore those big holes/trenches for sure!
This Milky Quartz and Fluorite plate was found discarded by the original miner on the dumps, cleaned up it is awesome, good enough for me! Just wish I could find the other material which made this trash in comparison!
These Fluorites were covered in pocket mud and then again in dirt. Always examine “dirt balls” !!! Needs some more cleaning, but examples of what you can find in the dumps. Fluorite and other crystals are heavier than other rocks, so pay attention to the weight of the rocks you are extracting!
First of all, what is float? It took me a while to get my head around this concept. My definition of float is simply any rocks or crystals that have weathered out of their original location — in other words Mother Nature has moved them via some process over time.
What could have moved the crystals? Glaciers, wind, rain, etc. Glacial movement is pretty easy to spot on the crystals, because they are broken, cleaved and/or have rounded corners like they’ve been in a rock tumbler. These crystals have been potentially moved long distances and there may be no correlation in where the crystals are located to where they originated from–in other words they may be randomly displaced and you may not find other related crystals around them. However I have found several times that pockets were moved (relatively) together by glaciers and there are concentrations of crystals that are completely worn in a somewhat small of an area.
Float coated smoky and milky quartz crystals found in a 10 foot diameter area about 6 inches under the ground. The left smoky is ~10 cm.
Wind and water (and ancient glaciers too) are common forces that move crystals from their original location in the seams/pockets they were grown in. Over the hundreds of millions of years (or perhaps just thousands, or even last month’s torrential rains?) the land has been eroded and the original locations of the crystals may have been partially or completely eroded away. If on a hill, the crystals are likely displaced downhill as they are eroded out of their original pocket. If on a flat area, crystals can disperse radially away from the pocket (which may at one time long ago been above you).
One misconception that I originally had about float was that the crystals would be laying atop the ground easy for the prospector to see. It took me a while to realize that float can be (and often is) buried. The layer of topsoil / organic matter is a recent addition to the ground (decomposed plants, trees, etc) in the perspective of geologic time. Most often I’ve discovered float that is buried in the boundary between the top soil and the granite gravel layers which can be visible or buried many feet deep. Note that with the hundred plus years of prospecting occurring in popular areas, it is very unlikely you’ll find crystals on the surface; but there is still plenty of float to be discovered!
Now that we’ve reviewed what float is in theory, how does one utilize this float concept to actually find crystals? When I find good signs on the ground I dig test holes (more about what are good signs in a minute). I try to dig deep enough so I’m at (or below) the boundary layer between the topsoil/organic matter and the gravel–the steeper the hills the likely this layer will be more shallow. I will also dig about a foot or sometimes two deeper to see if what I’m seeing at the surface continues in situ underground–signs of a pegmatite outcropping.
As I continue to explore the source of the float, I will dig an area of several feet in diameter, left and right, up and downhill. If I continue to find signs, then I will follow those signs in whatever direction they lead me, which typically trends uphill. The hope is that this investigation leads you to the originating crystal pocket or seam still in the pegmatite rock!
If there are no signs on the surface but the area in general looks or “feels” good, or if I’m feeling lucky, I dig test holes in best-guess locations and if I find nothing interesting within a 2-3 foot diameter, I move on to another spot.
I have also seen videos of folks using dowsing rods–the concept is they loosely hold L shaped rods in each hand and as they walk over an area with a crystal the rods will move. I keep thinking I should try this but I have no experience nor have done any research on this technique yet. Chime up in the comments if you’ve had success with this method!
A float dig. I was following signs up the hill (probably 10 feet here) digging only about 3-7 inches deep. Notice the pile of dirt on the right, this makes it ultra fast to fill in the hole once I’m done…literally 2 minutes. I often backfill the hole as I’m following the float. Notice the rocks on the surface above my digging, these are what you want to see, but in this case they are likely from another dig up the hill as they are not partially buried like Mother Nature would do.
What are good signs to follow? What do you look for on the surface to start digging there? How long do you follow the trail of good signs when they are not panning out? Well, that IS the trick, these are all the million dollar questions of prospecting! I’m still perfecting this myself and likely will be forever, but for now my answer is many things. Here is where joining up with a Crystal Club or digging with other prospectors is very helpful. I have found that even though I’ve read a ton on the topic and talked to many experienced prospectors, I didn’t really “get it” until I’ve gone and and moved some rock and dirt–experienced it; sometimes it even takes many times before what I’ve read or been told clicks. That said, however, I’ll try to give you some tips and rules of thumb based on what I look for.
You are looking for the following, above and/or below the surface as float or in situ:
Anything with flat sides. Train your eyes to see flat surfaces; having flat surfaces means there was enough room for the rocks to start to crystalize which is evidence of a crack, seam or pocket in the host rock. Finding flat sided rocks is integral in the hunt for crystals.
Quartz. Pegmatites are partially composed of quartz, so you are looking for chunks of quartz either by themselves or mixed with Microcline / Feldspar.
Microcline. Like quartz above, microcline or amazonite is a good sign.
Graphic Granite. Granite by definition is composed of small crystals of quartz and feldspar. Pegmatite is when the crystal sizes get to a certain size. Graphic granite / pegmatite is where these crystals get bigger TOGETHER. Often in just one rock sample you’ll see the crystal size increase from one side to the other! (see image below). This sometimes means you are getting closer to where the crystals can grow better (i.e. a pocket).
Combinations of above. This means that all the right ingredients of a pegmatite seam are floating out of somewhere.
Crystals. If you’re finding whole crystals or multiple sides, well, you’re there! Congratulations!
Here are some good examples of graphic granite from one of my digs. Notice the quartz crystals getting bigger in size and consistent through the rocks. Click the image for a larger picture with more detail.
These pieces of quartz are great signs with many sides–but none are totally faceted which tells me they came out of massive granite. Also notice the microcline. Follow these!
Example of a good mix of quartz on feldspar, almost (but not quite) starting to look like a plate of quartz crystals. The upper quartz has a several flat sides! This chunk definitely kept me on the hunt!
One other technique I use digging float uphill is when pulling out quartz or microcline chunks I leave them on top of my tailings pile close to the spot I found them. If I’m not finding the source of the float or lose track of the good signs (or when I take a water break), then I’ll often step back, take a break and review what I’m finding from a distance (which is possible because I left my findings consistently in sight on top of the tailings). This technique will let me analyze my current prospecting situation from a different perspective. While analyzing the rocks as I have dug up the hill, I will also analyze the surrounding hillside for clues like other digs, surface rock, contour, etc. Sometimes I get overzealous in my digging and forget this simple step-back-and-analyze step which can be really helpful in minimizing the search for the source of the float!
Another way to find crystals using the “float technique” is to start at someone else’s dig and start to explore around (if a flat area) and downhill of that prospect/hole. It’s likely that there is float around or below that pocket that someone else has done all the hard work and located for you! Many times the crystals are really nice and have just rolled down the hill a little bit!!! The original prospector was only interested in the pocket material and left all the easy float finding to someone else! I’ve found some really nice crystals using this technique!
Of course, the best place to dig is in crystal pockets. This is where the crystals will likely be the best quality and most plentiful (but not always, ask any experienced prospector and they will tell you stories of hours/days of work in fabulous looking pockets with junk, crushed or no crystals). Whether you happen upon a seam or pocket in the pegmatite using float prospecting techniques, or you find the peg right away and dive in, this is the goal of prospecting–to hit the mother lode!
First, a little bit of theory from what I have discovered in the field and also from reading and talking to other prospectors. I think of pegmatites as basically a lava flow of harder rock that when forming had the right (and larger) concentrations of minerals we are searching for. Because it is a flow, it often will be long and extend across or into the hillside and will often be somewhat straight. This is helpful to know as you often can follow the pegmatite as it trends in a somewhat straight direction across the hillside.
If the conditions were right at that instant of time millions and millions of years ago, you have highly mineralized fluid that was flowing through the cracks in the rocks. If there was room in the host rock’s cracks then it would give the fluid a chance to crystalize in that “open space” in the rocks. Because we’re talking about an extended “flow”, the pegmatite can open up (i.e. crystals!), then pinch out, and follow that pattern again and again along faults or cracks over its length. You sometimes see this play out when following the pegmatite getting pocket after pocket along the length of the peg! This is something to remember as a previous prospector may have found a great pocket but didn’t finish it or follow it as it opened up into even a larger pocket along the length of the original flow!
The great Blue Cap Productions video on Rhodochrosite at the Sweet Home Mine in Alma Colorado details that pockets were often found at the intersection of faults. I have found this to be true in some cases with pegmatites pockets I’ve found, as two pegmatites intersected there was a pocket. Additionally, Joe Dorris of Glacial Peak Mining has documented that when the pegs bend they often form pockets (which were eddies during the liquid phase?). This is also something I’ve experienced and definitely keep an eye out for.
Pegmatite is currently often surrounded by gravel or dirt. Over geologic time, the surrounding rock may have decomposed into gravel while the harder, more mineralized material is still in place. So once you are upon the pegmatite you’ll likely know its boundaries by gravel. Knowing this, I don’t spend much time when digging test holes if there is just gravel, but if there are chunks of peg, quartz or microcline then I continue as I may be digging into a pegmatite; and if I was into the peg and then enter into just gravel, I change my direction as I likely have found a border of the peg. When finding bigger chunks of rock, ensure they are pegmatite and not just solid granite. You won’t find many crystals if you are not in the pegmatite!
Note that have seen instances where all the surrounding rock is completely gone leaving just a trail of crystals in the gravel or dirt! So again none of these techniques is absolute each and every time!
I categorize the peg in a couple of ways, as described above (chunks) and also as solid masses (this digging takes the most effort). Sometimes I get into a peg that is still holding together as more massive rock and there is a seam sandwiched between top and bottom plates of granite. In that seam, especially when it has the opportunity to widen, I sometimes find small pockets of crystals. Following these openings the trail of crystals sometimes dives deeper; and that is where things can get interesting as you may be into a pocket. Note that these chunks of pegmatite can be quite large and heavy, requiring pry bars and even chisels and hand sledge hammers to extract, so ensure you are employing safe leverage and lifting techniques (a hurt back doesn’t allow one to dig for many crystals) and always wear eye protection! In these cases I follow the peg in all directions as the crack/seam may be rather long and wide but not very thick, but eventually it could widen and form a pocket. Here is a video example of this (these are HD video, so change the resolution if you have the bandwidth!).
So these are the techniques that I am currently using to find crystals. I am fairly successful in finding some crystals, but finding the great crystals or pockets is still somewhat elusive to me! My thought is it’s all about moving dirt and rock to maximize the chance of getting lucky. Comparing it to the lottery, you have to play to win! Regardless, employing these techniques has brought me success and hopefully will aid in your success too! As stated before, I would love to hear your techniques and ideas in the comments or by emailing me; I’m looking for any ways to improve!
Here are some videos showing me finding crystals out of a pegmatite pockets or seams. Pay attention to what is surrounding the areas with crystals as that is what you will be targeting when you dig! Additionally, I have accumulated a playlist of people extracting crystals from around the world, you’ll want to check it out!
For more articles on my prospecting adventures click here.
You should also check out the other blogs I follow with great information about prospecting in Colorado:
Was able to break away from our busy schedule and make a trip to Denver for a couple of the Denver Mineral Shows. As always we head to the Merchandise Mart for Zinn’s show as this is where all the display cases are. I have included many photos from these cases as there were some outstanding specimens on display this year. We also went to the Colosseum Show. I find that I don’t buy too many minerals, especially ones that I can find locally here in Colorado. Instead, I tend to focus spending my money on literature, display mounts and tools. I bought a subscription to the Mineralogical Record and man these are amazing journals! I suspect, although pricey, I’ll be a subscriber for a while. In the January/February 2015 issue on the fantastic Pederneira Mine in Brazil I learned much about pegmatites, some information relevant to where I dig!
Here are some of the cool minerals displayed in the specimen cabinets at the main show. Obviously a small selection as there were tons (literally) of beautiful and amazing minerals on display, just some that caught my eye. Many are Colorado or close-to Colorado specimens, a bit of scouting as I may pay a visit to those localities in the upcoming years!
Went up to Devils Head with the Lake George Gem and Mineral Club to do some pickin’ today. Last week the Fire Watch Tower / Campground area was hit with a EF0/EF1 tornado (max wind 90 mph, 500 yards long, 100 yards wide max) and is currently closed due to all the snapped trees. Luckily we didn’t go to that area and could continue with the field trip.
We went to the area east of the Topaz Picnic Area, near the old topaz mine and claims. I hadn’t had much luck in this area in the past, but it was good to hang out with like-minded folks and give it another try. I prospected an area that was level on the hillside with many other digs (this area is heavily dug) about 40 feet away, and about 40 feet or so below a really old dig. My goal was to either hope to find the pegmatite dike or perhaps find some float.
Immediately I found a clear quartz that was healed. I had to look carefully because it was amazingly clear and gemmy like topaz, but the growth lines on the crystal faces were perpendicular to the axis through the point and it had a quartz shape, so no go on my first topaz at Devils Head.
Dig area, following the float uphill
For those that often ask me what I’m looking for, this is something I didn’t find much online or in the books. This technique is just what I’ve figured out and there could be much better ways to prospect, but this will at least give you something to try the next time you are up digging if you are looking for things to try…
I scrape off the top soil to see what is at the boundry of the top soil and gravel layers…or “float”.
Clear Quartz in the sunlight makes it look like Topaz…
I continued to dig uphill (in the picture above I ended about 10 feet above the trees at the top of the photo) and as I got close to the old dig the quartz started to get larger. I was finding float, or quartz that is below the organic layer of dirt and above the gravel, or about up to 6 inches below the surface. Once I hit the clear quartz I started to dig around that, and then when I hit the first double terminated crystal I was able to form a trajectory up the hill and continued in that general direction. It took a little while to figure out the direction but once I did the area I had to prospect was smaller making the process quicker.
The double terminated smaller quartz was the second I found, and the larger double terminated quartz was the last I found at this location. Not pictured are all the shaped pieces of quartz (but not fully euhedral) that kept me on the chase up the hill.
Milky quartz crystals found while digging the float. The large one on the upper right was double terminated and so was the one in the lower left. The two in the middle show gemmy smoky quartz under the milky coating.
Double Terminated crystal shows several periods of growth. Original was likely to the pegmatite ceiling or floor, then it broke off and was healed (you can see this clearly on the other face).
Other folks were also having luck so it was a great day, the folks next to me pulled out a nice 4 inch smoky quartz! After my hole was filled in I got up to check out the finds of other folks, but most folks had already left, no wonder it had gotten quiet! I chatted with one other person who was in a small pocket in a very large dig and he had some nice crystals too.
I decided to try another spot and started to dig again after having lunch. Here I was able to find a small seam in harder pegmatite that produced some nice twin smoky quartz and some light blue amazonite crystal faces.
Overall a fun day pickin’ at Devils Head!
Smoky Quartz found in second location. The 4 crystals at the right were sidewall type crystals (the backs on a couple are not terminated). They were all found in a seam of pegmatite, not a pocket with sand, so it took a while to excavate from the small area.
You can see the white overgrowth on the otherwise gemmy smoky quartz
Amazonite found in the second location. More bluish than traditional green in color.
One thing about Devils Head crystals is they almost always need a bath as they have iron oxide staining, especially the amazonite/microcline. These photos above are of the crystals just rinsed of with water, showing exactly how they look when fresh out of the ground! The photos below are after a week of heated oxalic acid bath.
Soaked in a chemical bath for a week. Still some staining, but looking nicer!
Twin Smoky Quartz with lots of iron staining…needs a bath! Looks like it could be gemmy!
Nice etched polka dot patterns on the point!
Needs a good cleaning, but this Smoky Quartz is gemmy and also has some nice small crystal growth on the point. The back side is also terminated..really close to being a double terminated crystal!
It has been a while now that I have wanted to visit the Colorado School of Mines Geology Museum in Golden, Colorado. I’ve read articles about it, heard it was awesome, and still never have ventured to the far west side of the Metro to pay a visit. Well, the time had come; my daughter had a Girl Scout event at the School of Mines earlier this year and while waiting for her event to finish the rest of the family went to the museum…and we’re glad we did! It did not disappoint; the local Colorado collections they had were outstanding!
What I liked most was the fact that they had similar specimens from popular Colorado localities that I have collected. In most all cases their examples of the mineral(s) were much better than I have, but in a few examples I have found similar quality specimens from the same localities. Because I have been to the same location as these were unearthed from; I also was able to definitively identify several specimens that I was only partially sure about!
There were also several specimens that I really like that I have not found that mineral anywhere yet; but they were so cool that I had to take a photo of it anyway. The museum is full of wonderful specimens — these pictures don’t do it justice; you have to *BE* there to truly grasp the magnitude of the beauty of these specimens, but hopefully the pictures get you itching to visit Golden on your next trip to the metro area!
A person at the colosseum show a couple years ago had several of these for sale for cheap. I bought one in the same league than this!
Oklahoma Galena, this is an awesome specimen! As a storm chaser I remember when Picher was partially destroyed by a tornado in 2008…what I didn’t realize is that it was a Superfund site and is one of the most toxic places in the US. Picher is a modern day ghost town for a good reason!