Last weekend I had the opportunity to participate in the Colorado State of MInd event sponsored by the Castle Rock branch of the Douglas County Libraries. A friend works there and asked if I could present the rocks and crystals I have found in the state. Sounded like a ton of fun, literally!
My bland booth, chock full of rocks
I worked the entire event, 5 hours, talking to very interesting adults and super cool (and many times very intelligent!) kiddos on crystals and rocks. Everyone could pick up the crystals and experience their beauty and geometry up close. I really enjoyed seeing the excitement of the kids faces as they explored the beautiful rocks, and enjoyed meeting like minded folks. I think many people were amazed of the cool gems that lay underground in literally our back yards!
Dave and library patron Carl Degolier. Kindly used with permission from DCL.
I talked about some useful information, so I thought I’d include that information here for reference…
This summer was great, but different than previous, for picking and rockhounding. My club field trip availability was limited–I led two trips and was able to make only one other. I went to Gem-o-rama in California with a rockhound buddy (see other blog post for that adventure). The remainder of my rockhounding trips this summer revolved around a pocket I uncovered during one of the club field trips I went on. I didn’t get out nearly as many times as I have in previous years; but the times I did get out were all high quality, extremely fun and productive! 2016 I would say it was a very successful season!
NOTE: As always, click on the pictures for a HD version. Trust me, it’s worth it! The videos are all available in HD as well.
On my third club field trip of the year I hit into a pocket that consumed 5 days of hard and thrilling work in the following month. It was the biggest crystal pocket I’ve ever found and had some really interesting and amazing crystals. It took me until the very last day of digging to think of the proper name for this pocket…over the month I continually thought about the pocket and realized I had a crush on it…and most of the crystals were damaged due to ancient violence, so I figured the name “Crush” described the experience perfectly!
Here is a _very_ rough drawing of the pocket. Note I have little artistic skills, lol! You can see where I entered in the upper right. The crystal pocket measured about 4 meters long, 0.6 meter diameter and the bottom was 1.5 meters underground.
It all started with a test hole about a meter from the pocket. From others’ experience in this area I knew that crystal pockets tended to be rather deep, so all my test holes need to go at least 1/2 meter deep. When the hole was about a meter diameter, I started to see a shift in color of the soil to a darker brown so I followed it–it was a subtle sign, but something “different” is often what leads you on the crystal trail! Not too much further I started to get into small chips of quartz which quickly turned into a layer of small quartz chips. These chips had no faces or flat sides. Breaking through that layer I entered a zone of darker material and started finding crystal faces. I was in the top of the pocket!
The first crystal plate/cluster I pulled out of the top of the pocket. I’d say that is a good sign of things to come!
This whole top and side of the pocket (along most of its length, except the ends) was softer clevlandite/feldspar material with large chunks of quartz buried here and there within; these quartz plates had beautiful secondary growth clear quartz all over one side, but in this layer nothing was fully euhedral. This layer of the pocket was about 10-25 centimeters thick and produced some nice plates of parallel growth clear quartz.
I continued to follow this trend horizontally (to bottom and right in the above diagram) until I reached the end of the pocket material — I was back into normal top soil-dirt and gravel underneath. That is when I started to excavate straight down. It was just a few minutes and then I hit extremely red pocket dirt/mud material which is the tell-tale sign of a crystal pocket! For the rest of the day I continued to pull out more of the same type of secondary growth plates and individual crystals with secondary overgrowth. Some really neat and unique crystals!
This was the largest plate I pulled out on the first day. The flow of the crystals is evident, this is about 30 cm wide. Note that the crystals change direction in the middle of the plate so they are pointing toward each other. I’m sure there is a reason for this, hit me up in the comments if you know why that would be! You’ll want to click on this image for a close up!
This is a really interesting crystal, I love the large terminated crystal surrounded with the smaller parallel growth, and then the different type of cluster growth at the bottom, first small then larger–all of this on the same plate! Also, the crystals at the very top are pointing down and immediately they reverse.
Thanks to Matt who was also on the field trip for taking this shot; I was back filling the hole as I progressed down. I was still only about 1/2 way through the depth of the pocket here. What an awesome day!
I thought I was nearing the end of the pocket at this time, so I buried the hole and packed up for the day knowing I’d come back in a few days, excavate the hole, and finish it off. It turned out not going the way that I planned…
Given the pocket was trending downwards, my plan for the second day was to remove the overburden over the deepest part of the hole and also widen the hole so I could continue picking crystals starting with a large crystal I already partially uncovered. Its good to have a plan, but its also good to be flexible! As I was mucking, I noticed that there was more of the pocket heading the other way (i.e. in the direction of the picture taker in the above shot). I ended up focusing on that direction for the entire day as the pocket continued, and got better (!!), in the opposite direction than I originally planned!
The pocket continued as described with the crystal plates at the top and side; but as I progressed I noticed that the floor of the pocket had a layer of larger more well formed crystals and finally microcline at the bottom before it ended up gravel. So I was now seeing the entire dimension of the pocket, about 2/3 meter tall and 1/2 meter wide.
An hour or so later, in the center of the pocket, the red mud/clay turned to purple in a couple of spots; that is when I started to find some small fluorite crystals. These fluorites were a truncated octahedron shape, kinda like a soccer ball. They started out really small (~1 cm) in single crystals but then out came out in small plates. A 1/4 meter further, along the side wall of the pocket, the fluorites started to get rather large, up to 8 cm. At the same time the bottom of the pocket had a couple of large quartz crystals.
This is one of the larger fluorite crystals I pulled out, definitely the largest on the second day. Note that the square sides do not have any coatings; but the other sides have a purple coating. Really interesting!
This is an example of a truncated octahedron. The fluorite crystals I found were very close to this, however only a few of the smaller ones were completely euhedral. The larger ones were about 1/2 of what is shown here.
This is the large quartz that was sitting on the bottom of the pocket. Three of the sides were covered in the secondary growth terminating with larger crystals at the top. It had a small cluster of fluorite on the right side, which was the direction where I was pulling out the fluorite mini-soccer balls. This was the largest crystal that came out of the pocket although it wasn’t euhedral!
The pocket didn’t show any signs of stopping, and all of a sudden it was dark. The nearly full moon was illuminating the ground through the trees. I was exhausted but needed to fill in the hole. So I started that tedious process and a little while later realized I was surrounded by coyotes…they must have killed something because they were screeching and barking in all directions! The whole experience made me think Edgar Allen Poe…the evening ended with the soundtrack of me filling in a large hole by the moonlight…what is going on in them woods after dark?
So as many of you that pick crystals know; when your into the crystals and have to leave a pocket, you continuously think about the pocket while waiting for your next trip! I’m no different and since I knew it was going to be a week before I could head back up, I couldn’t help but go through the fantasy scenarios and put together a plan of attack for that next trip. My plan was to excavate the far end of the pocket I was in day 1, taking out the overburden, widening the hole and pulling out the large crystal that was “stuck” and generally seeing how long that side of the pocket continued. Then, if I extinguished that side of the pocket, I would dig a new hole on the left side (again see diagram above) and meet up with where I left off after day 2. This would be less work by minimizing the mucking and centering the next portal along a new section of the pocket!
I had my plan and was able to take a day off of work a little over a week later. I decided I’d head up after work and set up camp, do the mucking of the hole and then go to sleep; waking up at the crack of dawn and start plucking crystals on my day off. Ended up getting a later start then I planned and it was dark by the time I arrived. I lit the lantern, set up camp, and then started the mucking which took a while. Of course, my plan was flawed because there is no way I can expose a crystal and not try to remove it! So I ended up working on the pocket until 2 am when my headlamp batteries started to dim! I then watched a meteorite shower and hit the sack.
The next morning I went down and continued with that side of the pocket until it pinched out. I was able to remove several large crystals (seen in the video) and behind these crystals the pocket pinched out. I hit nothing for the next 1/2 meter so I felt I reached that end of the pocket. After taking a break I started with phase two of my plan. I hit the end of my day 2 digs a couple of hours later and was back into the crystals. Once back into the pocket I was able to pull out a large chunk of fluorite along the side of the pocket (top side in the diagram). The fluorite came out in many pieces (totaling ~30 cm long, 5 cm tall and 5 cm wide). This was exciting because the fluorites were continuing to getting bigger the more I went in this direction! However, that was the last fluorite I found in the pocket. This large chunk was EXTREMELY brittle and broken up and much of it ended up disintegrating when I tried to rinse it off with water.
This was part of the large chunk of fluorite–the part that didn’t fully disintegrate when I was washing off the pocket mud!
These were some of the large crystals I pulled out right before the pocket pinched out on the right side. The crystal in the center is about 18 cm in diameter, has a lot of healed terminations, and fits perfectly with the other crystal that was found nearby in the pocket (see video)! These crystals do have damage–as most crystals did in this pocket (hence the pocket’s name)–but still was a thrill to find!
The hole after day 3, again back filling (on the right) to minimize the mucking efforts.
As you can see in the picture, it was awkward and difficult to go to the bottom of the pocket with that overburden there, so on day 4 I removed it. I then spent the remainder of that day taking out the bottom of the pocket and following it further. This section of the pocket started to change from the consistent topography I was getting used to. The top of the pocket had less of the softer clevlandite/feldspar than before and was more interlocked quartz and pegmatite. The number of crystals on the top was significantly less than before; the ones that I found were more euhedral and still coated with secondary growth. This side seemed to be where the most violence had occurred because there was a lot of damage to most of the crystals. The clay was also harder and pulling the crystals out without damaging them further made progress considerably slower. There was no more fluorite found on this side of the pocket.
After day #4, I added the wooden dam so I didn’t have to worry about the other side of the hole continuously filling in while I was mucking and working the pocket. I had started filling the hole before I took this picture, the bottom is another 1/3 meter buried.
The fifth day ended up being the final day. I was able to pull out a couple more really nice crystals as the pocket started to dive under a pegmatite rhine. The crystals below this point were no longer coated with secondary growth and all were intergrown and not fully euhedral. Many were still large. Once the pocket started to dive downward, the sides of the pocket were difficult digging and the crystals weren’t the quality to pursue further. The pocket had finally pinched out! I decided to throw in the towel and celebrate the amazing crystal pocket I had unearthed!
Here are the last crystals I pulled out before it got too uncomfortable to dig and the quality wasn’t worth pursuing any longer. The end of an amazing pocket!
Cleaning these crystals has been a chore. They had many phases of growth, first the smoky quartz, then a layer of albite, then a layer of iron oxide, then a layer of clear secondary growth quartz, then another layer of iron oxide and clay. Cleaning these requires a chemical bath and then mechanical cleaning, repeating over and over due to the tremendous amounts of facets that each crystal has. Because there is a layer of iron oxide under the clear quartz, the crystals are somewhat “spotted” with red and white that can’t be removed from under the clear quartz. In some instances they beg to be cleaned more, but then you realize that the staining is all under the clear quartz.
The amount of facets are amazing and each piece, regardless of how little or large–they are all unique! I will probably leave some pieces uncleaned as they will look better that way; while others I’ll spend the winter cleaning. It takes about 2-3 weeks per batch of crystals to get them clean enough for my liking (several iterations of chemical then mechanical cleaning), so it is a slow and labor intensive process. But a day playing with crystals is better than a day at work, that’s for sure! This will add some fun throughout the entire winter!
Here is a gallery of some of the crystals and plates that I found.
These were some of the large crystals I pulled out right before the pocket pinched out.
Been awhile since I have experienced late night lightning, but I was awake and in luck tonight, Aug 28th, 2016. We had taken a trip to the Arkansas River valley in southern Colorado to buy Pueblo peppers and visit the state fair where my kids had participated at the State level in 4-H earlier in the week. After a fun but long day we came home and I started peeling the skins off of our many bushels of peppers; this usually goes well into the night! Just as I was finishing bushel #1, there were flashes in the sky; at first I thought it was a car going by but to my delight a storm was passing by to our south.
The insects were having a symphony in the front yard and the only man-made noise was a train passing by a 1/2 mile or so away (lots of squeaks and metal on metal scrapes) so I recorded some of the ambience while enjoying it. Meanwhile the lightning was becoming more frequent, so i jumped in the car and headed for vistas out of the trees. I ended up driving about 5 miles south of Larkspur and sat on top of a hill overlooking the Spruce Meadows Open Space at Greenland and watched the show.
I enjoy taking pictures of lightning with power lines, and these were carrying a lot of electricity so I figured it would be perfect foreground for lightning shots. Given it was raining and the lightning was fairly close, I decided to shoot from within the truck. I have been getting better at holding the camera fairly steady with the iris open, these were 6 second shots at ISO 800, f/11, focus at infinity. I was using a wide angle lens.
To remove the rain from the windshield I need to have the wipers on; sometimes there are drops in the shot but that goes with the territory; not much I can do about that given it is raining. Luckily the lightning is so quick and otherwise it is dark (no light) so most of the shots you don’t see the wipers. Then it is just a waiting game, reviewing the pictures to ensure the field of view is what is expected. Unfortunately the lightning was infrequent, about 90 seconds apart, so I got a lot of black pictures I had to delete later.
As always, click on the photo for a larger size.
Interesting placement of the bolt and the tower, I wish I could say it was planned, but nothing about that shot was planned; all luck…and being in the right place at the right time!
Lots going on in this shot, it was very bright!
One of the last anvil crawler style bolts of the evening, just before midnight; the last one was massive (there was about 5 minutes between it and the previous) and it was so bright and long that I moved the camera (I have to admit I was getting tired and it startled me) and the picture was blurred/jittery.
Close-up of the previous shot (lower right) showing three upward streamers, the right most one got the return strike but was a bit off from the original streamer (or there were 4).
If only we could harness that…looks like it almost tapped us!
Cool black and white shot, south Douglas County Colorado, Aug 28th about 11:30pm.
We love visiting Rifle Falls State Park in western Colorado, this is the fourth time we’ve stayed there. Rifle Falls SP is north of Rifle and New Castle which are Interstate 70 towns, and is about 25 miles NW of Glenwood Springs Colorado. It is a small park and is co-managed with Rifle Gap State Park several miles to the west. There are tent camping sites along the small creek with a good amount of privacy. Pull-in sites have electricity and will accommodate pop-ups to motor homes. There is potable water available at several taps in the campsites. There are a couple of non-flush bathrooms making those early morning trips convenient.
Beyond the campsites is parking and picnic areas at the main attraction, the three waterfalls. Over the weekend the park was heavily visited, so we hung out at the very well shaded tent campsites with our chairs and feet in the creek, occasionally taking plunges in the pools of cold, refreshing Colorado stream. In the evenings we hung out in the luxury of our friends pop-up camper and had a great campfire.
There are hikes around the tent sites, a loop around the falls, and a loop to the neighboring fish hatchery. There are many caves along the falls loop where you can go inside and enjoy some darkness. Nighttime boasts dark skies in the canyon. Overall a fun multi-family camping experience!
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.
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!
Here are some of the petrified wood pieces that I picked up at my friend’s property in Northeastern Douglas County in Colorado this last weekend. The wood in Douglas County dates back up to 55 million years ago. To put this in perspective, the last phase of tectonic activity formed Rocky Mountains around 80-55 million years ago; so these are wood from the forests on the craggy, new Rocky Mountains! Interestingly, much more recently in time (about 100ish years ago), wood forested from the Palmer Divide was used to build cities like Denver. Forests have covered the land here in east-central Colorado for a long time!
So how did I find it, well, I just walked around and picked it up off of the ground, for the most part. It tended to be all together, so once I found something on the surface, I could search around that area and find more. I also tried digging some, and there was more under the surface as well.
Was playing around with some settings on the new Sony A7R mk2 camera, and experimenting with the wonderful ice we’ve accumulated due to the great February snowstorm. I so far am really enjoying this camera!
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:
I love the monsoon season, because 30% chance of thunderstorms means there will be one within 30 minutes of where I live; it is the way living atop the Palmer Divide usually works! I drove about 10 minutes south of home and was able to capture these tonight. Not as close as yesterday’s lightning by any means, but still pretty cool. Again, cell phone and daytime pictures so quality is appropriate, daytime lightning is much harder to photograph, especially getting the stepped leaders! What will tomorrow bring?