Rockin the Rockies

Rockin the Rockies
Rock Hounding

Wednesday, July 6, 2022

Jack Dempsey Pocket #crystal mining #rock hounding #Colorado

I found this pocket on 24 June which just happened to
be Jack Dempsey's birthday. Dempsey was a champion professional boxer, and Colorado native.  The pocket was pretty beat up, just like some of Dempsy's opponents. 

I prospected an area a few days earlier and tried to dig there but Mother Nature kept sand blasting me with very strong winds. I ended up looking further down the hill with no positive results. I resolved to come back to this more promising spot. The next time I went out, the winds had abated, and we had a real nice day for prospecting.  I found a fairly strong quartz seam and so I decided to follow the seam and see what it might produce.  A couple of large dirt-covered rocks which I assumed were goethite soon popped up. Upon further inspection I found them to be fluorite.  Nothing spectacular, but off to a good start. The fluorite has a clear center with a green outer layer then purple.

Multicolored fluorite
The exterior was coated in an almost drusy coating of purple fluorite crystals. I continued to dig the quartz seam. Many of the quartz chunks started to have a face or two so I continued onward.  Soon I was down about 4 feet, still following the quartz seam and trying to decide whether or not to continue.  The seam was expanding. After a bit I found a couple of quartz shards with crystal faces and knew I should continue.  At about 2PM and 5 ft down I hit a pocket of sorts.  Massive quartz chunks many with faces extending down into a clayish material. The pocket!  I carefully excavated some of the larger quartz crystals before I called Bob over. Below you can see some pictures of the excavation in progress. The first picture displays the largest complete crystal angling down into the pocket.  The second picture below shows me holding that same crystal outside the pocket. 

Crystal in pocket debris

 After pulling out a 7 incher I let Bob have a turn.  I had been digging for nearly 5 hours straight and decided I needed a break. You get tired and lazy with time and then start breaking crystals.  Bob was happy to give me a break and he quickly found some large crystals just to the right of my quartz group (pictured above). All Bobs finds were disconnected from the matrix and were laying nearly horizontal in the clay. Bob got one 7-incher but the termination was broken off.  A minute later he found the termination to it, so now an 8-inch crystal.  I decided I better get back in the hole before he got all the good ones. Haha. I found mostly broken crystals and called it a day, to resume the adventure next time out.

Next day we came out I went to the back wall of the pocket and found a lot of microcline plates and some flat plates with nearly clear quartz crystals protruding from them. Below this layer was some microcline and below that was the mud with embedded quartz crystals. As I got into the quartz layer and mud, I started seeing some humongous crystal forms. 

What I thought at first was at least an 18 inch crystal.... aw shucks!

It took me almost an hour to dig out this one crystal only to realize 3/4 of the way through the process that I most likely had a crystal that had no termination.  It was becoming obvious the end of the crystal ended in the side wall of the pocket.  The crystal was also attached to the pocket floor in several spots. Later I found another similar crystal but let Bob dig that one out.  Sure enough, that crystal also ended with no termination.  I kept looking for fluorite but found none after the first two examples the previous day.  I continued digging out the bottom and back wall and only found dozens of broken quartz crystals and a few plates of microcline.  I was pretty discouraged that after 2 full days of work I had not found many collectible crystals. The number of broken crystals was amazing.  I went home for the day realizing I was probably done with this pocket and had a lot of remediation to do.

Next visit, I figured I better check everything over one more time before I filled my 5-foot hole.  Once I fill this in there will be no going back to redo it. I definitely don't want any diggers remorse thinking, what if I had dug here or a little over there...  I double checked everything. I pulled out country rocks from the pocket floor, checked the sides and even backed up a bit.  I found a few 2-inch quartz crystals but nothing I would have regretted leaving.  Toward the end of the day, I found one fairly large microcline crystal and put that in my shirt pocket.  I left most of the microcline plates at the dig site. While the plates of microcline were large, the microclines were fairly small and spotted with iron material... yard rocks at best. I spent about 2 hours remediating the dig and probably have a little bit more to do. The weather began to turn south, and lightning started to crackle nearby.  On the drive home Bob commented on the fact I seem to have a knack for finding microcline twins.  I had only found one baveno twin, not much considering all the microcline I dug out. It was then that I reached into my shirt pocket to take a look at the silver dollar size microcline I found earlier. It was the last crystal I took from the dig. I wiped a bit of mud off it and sure enough it was a Mannebach twin. 

Twin common plane with chevron notch at top 

Many years earlier I found a pocket that I called the Waste of Time pocket.  This was a close second to that find.  Still, digging for hours and sifting through material is fun. You never know what might turn up. All in all, I still enjoyed a very nice time in the forest.

When I got home, there is the sorting and cleaning process.  A couple small surprises included fluorite attached to some of the smoky quartz crystals. Noticed a few microcline plates that included smokeys. After looking at the crystals it seemed the crystal pocket went through various crystal building events. 

Purple fluorites on quartz crystal.



The pocket was first formed with crystals that were irradiated and became smoky. Something in the pocket then etched many of the smokys. Next was a secondary infusion of quartz which coated many of the first-generation etched crystals with a clearer layer of quartz. This event created hooded or phantom quartz crystals. Next up was some fluorine in solution. There are chunks of fluorite as pictured above. Some of the clearer second-generation quartz crystals have small fluorites attached to them as well. At some point some albite and iron oxides also came into the pocket to add some variety. Of course, this is only a hypothesis, and I am sure some will disagree with my conclusions.

                     
Left pic is typical quartz crystals from the pocket, just too few for the level of effort expended

I may post more pictures of the specimens collected at a later day.  Now I'm off in search of another pocket of crystals :-)