Rockin the Rockies

Rockin the Rockies
Rock Hounding

Saturday, July 4, 2020

June Diggings and the Potentilla Pocket in the Lake George Ring System of the Pikes Peak Batholith, Colorado #Crystals

                               Potentilla Bush near my new dig                  
I'm calling this the Potentilla Pocket because there was a potentilla bush nearby. Always go for alliteration when you can use it.😏  The previous year in June I discovered a pocket about 100ft down the hill, that I called the "Indian Paintbrush Pocket"  I'm hoping to name several more pockets on this hill after plants.
I discovered a pegmatite last year and found a couple of small pockets which contained both amazonite and smoky quartz crystals.  The pockets were small but the color of the amazonite and luster of the smoky quartz pushed me to spend more time there.  I had stopped digging this pegmatite as the quartz had pretty much disappeared and a large potentilla/cinquefoil bush stood in my way.  I didn't realize the cinquefoil was an invasive species or I would have torn it out and kept digging.  Well, I decided to start digging just up the hill and left of the bush and immediately hit the pegmatite I had been previously digging.  Hmmm, lots of quartz in the rock!  I immediately started lifting out pieces of pegmatite and was rewarded with a few shards of quartz, then a small crystal.  I decided to call Bob, my digging partner over.  Usually I wait til I find something before I call Bob, but I was pretty sure I had something. Soon tabby quartz crystals started to appear as I dug in a bit further. Then shards of sharp quartz.  Thin quartz shards are the best indicator I know of that you are coming into a pocket, that and clay or a change in the dirt's color.  I found a few tabbies and then noted a spot of blue/green color.  The light blue color indicating amazonite wasn't great, but I never turn up my nose at amazonite.  Time to down shift and put away the pick axe. Careful probing with my rock hammer and scratcher are needed as I slow down my excavating and take more care as I proceed. Continuing to dig down I noted a few more quartz crystals and a mound like structure of feldspar.
     Nice little cluster of amazonite with clay           
The mound of feldspar was shedding amazonite crystals all along it's right side. Bingo! While the crystals were not super blue/green nor very big, they were very sharp and somewhat elongated. The sharpness of the crystals and perpendicular growth from the matrix makes them desirable to me.  Bob was duly impressed as well. I loaded up my backpack at the end of the day and let Bob inspect the pocket while I packed up. 
Another cluster of amazonite after a soapy rinse
                Bob didn't find any more crystals but did mention I better check the wall of the pocket because there was a lot more of those shards of quartz spilling out on the uphill side of the dig.
There were a lot of "crumbly/shards" of quartz on the edge of the pocket I had dug out so that is where I would put my efforts next. We have been having trouble with claim jumpers on weekends so I determined to hit that pocket again before the weekend. 
             A lot of damaged smoky quartz :-(            
I arrived at the claim before Bob and within 10 minutes of digging the sidewall of my former pocket I opened up another crystal bearing cavity. I hit two more mounds at the bottom of this pocket and a seam running along the upper edge of the pocket.  The seam was an area of discontinuity between the country rock / granite above and the more mineralized quartz pegmatite below. This pocket seemed to be composed of nearly all quartz crystals.  Many of the quartz crystals were broken, but not all of them.  I found a few handfuls of smokies and some beat up
amazonite smoky combinations. I thought of what could have been here.  I spent 2 days on this second pocket or more likely an extension of the first pocket.  I carefully worked the pocket down and all around the perimeter. When you hit country rock less mineralized/more fine grained granite) you know you're done.  I always pull down a little of the sidewall (country rock) just to make sure there isn't anything hiding behind it. I had told my friend Austin that I would be at the claim and he should come on out. Austin found me at nearly days end.  He had found a few floater pieces, one large amazonite that really caught my eye, but he hadn't found the source. I decided after 6 hours of digging in the sun that I was ready to finish up. Austin volunteered to work the dig while I wrapped my prizes. Austin found a few small crystals for himself as I got ready to go. He also hit a number of pseudomorphs near the bottom of this pocket. Behind the pseudomorphs was a layer of sandy like material with a few more crystals that I found the next time out. This was a fairly good pocket but falls short of being called one of my top 10 pockets. Two things held this pocket back from being more notable. The extreme amount of damage gave me almost no chance for collectible combinations of smoky quartz and amazonite.  Many of the smokies were also rehealed, so fitting pieces together was impractical. If the pocket had less damage to it, it would have been superb.😁 The color of the amazonite was also more of a greyish green than blue/green.  I believe a void I discovered at the bottom of the pocket may be why there was no clay in the pocket.  The clay material for the most part just leached out of the bottom.  A lack of a cushion of clay within the pocket resulted in the extraordinary damage to the encased crystals. Still worth a hurrah! Anytime you find a pocket with a diameter over 2 feet I feel it is significant.
Day 3 at the pocket was spent double checking for any extension of the pegmatite to see if I could follow it any further up the hill.  I went another 5 feet up the hill, but no quartz and little in the way of any larger grained granite pieces. Time to remediate the hole. Where did Austin go?
Time to fill in the hole
First you put in the big rocks, then the medium rocks and then the dirt.  Mother Nature does the rest.

    Next couple trips out I did a lot of prospecting.  Anytime I see some old digs and amazonite chips scattered around I take a closer look.  This one day I saw just that. It looked like somebody knew what they were doing so I didn't give the spot much hope but thought I might scrape through the dig tailings to see what my predecessors had found.  As I searched around I noticed a fairly new fall of a burned out tree on the edge of an old pocket. Hmmm.  These digs looked really old and I'll bet that tree was green and standing when these holes were dug.  The area we are digging in was burned by the Hayman fire several years ago. 
           Large overturned tree with roots         
 

I checked out the overturned root of the tree and found some amazonite still clinging to the dried out root.  I guess I'll poke around here for a bit. Within inches of the topsoil I found well-formed amazonite. The amazonite was small but had a nice blue color to it.  I continued to dig out the quartz with amazonite and soon I happened upon a yellowish clay and found a small pocket.  The small pocket went down into the ground about 6 inches.  I found a few amazonite crystals along the periphery of the pocket. At the bottom of the pocket were a few smoky quartz shards. This dig wasn't very big but the quality was much better than the previous pocket I mentioned above. No quartz crystals were in the pocket, just mainly single amazonites. 
Picture
Picture courtesy Bob Germano
Pictured is the best of the lot.  



I continued to prospect this old dig area but found nothing else worth mentioning.  I may return here on a cooler day and check some more old digs another time.  That is pretty much it for June.  One large dig that took me 3 days to finish and one smaller dig I cleaned out in an afternoon.  The rest of the time was spent prospecting. Towards the end of June I found a well developed pegmatite hiding under some "rice rock" which will give me something to do in July.  I've pulled some of the rice rock / cap rock off the pegmatite and am finding some microcline crystals associated with a fairly strong quartz layer.

Hail on the west side of Pikes Peak from Lake George, Colorado





2 comments:

  1. My boyfriend and I are new to rock hounding. We have gone to a few different places near manitou springs, but haven’t had much luck. Any suggestions to a newbie on how to spot a pocket? We planned on going out toward Lake George this weekend, that’s how i found your blog. Any help would be greatly appreciated :)

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  2. Best thing to do is join a Rock Club... If in the Springs try Colorado Springs Mineralogical Society. They are doing occasional field trips. They have a couple claims near L George and will show you the ropes and keep you out of trouble/claim jumping.

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