Rockhounding at an Estate Sale in Colorado Springs

Rock hounding at an Estate Sale is like shooting fish in a barrel.  Not sure where this idiom came from, who wants a bunch of shot up fish, I guess they are easier to catch that way and maybe some are already disemboweled/cleaned. The rocks at the Estate Sale were easy to catch and already cleaned for the most part.
An avid rock collector from my Club had to move for health reasons and couldn't take her rock collection with her. The manager of the estate sale said she didn't want any rocks left over and wanted the specimens priced to sell. Better to sell the minerals cheaply than have them dumped in a landfill, so sold they were. After the end of the first day of the sale a gentleman purchased the rest of the collection for half off the already deeply discounted retail prices. I'm not sure what he will do with all the specimens, many of them duplicates, but maybe he will have a rock store of his own some day. As a collector I was glad I didn't wait to purchase any of the minerals on the second day of the sale, as none would have been left.
Going into the sale I wasn't sure what to expect, I knew the collector was primarily interested in micromounts (small specimens) but I hoped the collection would also be stocked in larger Colorado minerals like Stoneham barite, fluorite and possibly some smoky quartz and amazonite pieces for my collection. I was surprised not only by the quantity, but also the diversity of the collection. It was also good to see many of the minerals had tags with good provenance. I set a maximum of $100 to spend, but was soon near that limit. I found several crystals that I had on my wish list, but had not expected to find them at the estate sale. Among my purchases were cavansite, crocoite, apophyllite, fluorite, a surprise Faden quartz specimen and a Stoneham barite. I also purchased a microscope in working order, but with missing parts (easily rectified). As I was going through the mineral specimens I decided I wouldn't want my collection dispersed this way. Not only were the minerals going for low prices, but the collection had placed a burden on others for disposition. At least the minerals went to collectors. I think when I reach 3 score and 10 years it will be time to part with all but the best. DV.

See Pictures Below

Apophyllite from India





Huamalies Province, Peru



Magaliesberg, South Africa



Cavansite from Loc-Wagholi Pune Maharashtra State, India




Creedite from Mexico



Dundas Tasmania, Australia
 




North Waziristan, Pakistan (Highly Prized by Me)





Peruvian Pyrite




Quartz Float

When a crystal pocket is exposed, the process of weathering will gradually move the crystals down hill. Sometimes this process can be very slow or happen quickly depending on circumstances like steepness of the hill the pocket is on or amount of precipitation that moves crystals downhill. Float quartz is any quartz that has moved away from the pocket either due to the pockets initial breakage or through weathering. Quite often when prospecting you will find float quartz below the pocket (on a hill) and then prospect up the hill to find the source of the float quartz -- hopefully a quartz pocket. Last week I had found a pocket of crystals without prospecting below the hill up to the pocket. As my rock hounding buddy would say, I dumbed into the pocket. I decided I needed to prospect below the pocket. I found some nice quartz crystals which were actually larger than the crystals in the pocket. So I prospected the hill above the pocket and found no crystals. Just an anomaly I guess.
Today I went back to an old site that I had prospected and found nice float crystals, but never found a pocket. Today was just the same. I found some nice float crystals, mostly 2-6" below the surface, but no pocket. The crystals were somewhat damaged but still collectible in my mind (see below). The crystals are 3-4" in length all have minor damage to varying degree. I have dug up the area extensively and believe there was an old water wash in the area. The crystals seem to be collected around boulders running down the hill (like gold in a stream I guess). Nearly 50 feet up the rather shallow hill there was a pocket with what I surmise were nice crystals and I can only guess the quartz float I am finding comes from the old crystal pocket. I have prospected the entire 50ft up to the old pocket and granite contact zone with no success.  I have spent about 7 days last year digging this hill with no pocket results. I shall probably try the area again, but don't want to waste my entire summer digging through float :-)

A little HF might sparkle these up some, not sure its worth it considering existing damage

This one is 4 inches, somewhat dinged, but still collectible in my mind

Smoky Quartz at Lake George

Normally I go rock hounding 2-3 times a week. The past two weeks I have only gone once a week due do to other commitments. Last week I found a small but productive pegmatite towards the end of the day with many small smoky quartz crystals. Seeing as it was the end of the day and I had a HS graduation party to go to I buried the pegmatite. I had not been able to get back until yesterday and probably won't go again this week due to my rock club (CSMS) having its rock and mineral fair this weekend. At the fair, I will display petrified wood and my digging friend will show off his Lake George finds. I think people will be surprised at the quality of the crystals Bob will display, but that is for another entry.
I dug out the pegmatite yesterday and once again found many small smoky quartz crystals. Most of the crystals were less than 1" in length. The crystals were very gemmy, but never attained any length or girth. I was somewhat puzzled by the availability of pegmatite quartz and lack of any larger crystals. The pegmatite was also very close to the surface. After digging out the pocket I decided to dig below the pocket (down the hill) and work up to the pocket. Hoping to catch some float crystals. This paid off. Despite the slope being very shallow (maybe 5 degrees) there were float crystals that were better than anything I found in the pocket. Hoping that there was another pegmatite that I might have missed between the float and my pocket up the hill, I continued to dig up the hill and work down every time I found a crystal. Unfortunately it appears the float did come from the original pocket. Still I was glad I had taken the time to go down the hill and work up to the pocket finding some nice gemmy 2" float crystals with very nice terminations. Often float crystals are more damaged than crystals you find in pegmatite pockets, but this was not the case with the float I found.
As the day winded down, I took some time to prospect the area more and almost immediately found smokys. These crystals were also small and hooded (see example below). I also found a nice piece of amazonite on my hike out. I'll have to prospect that area as well. Much to do at this site, may keep Bob and myself busy all summer... stay tuned.

Float Crystal 2" Chisel Point

Float Crystal Drill Bit Point

Odd Hooded Crystal

Field Trip for Tourmaline

Tourmaline in the Rockies can be found, but is often not the real gemmy crystals that people make jewelry out of or sell for big money. As a crystal collector I find the form and luster of tourmaline/schorl desirable NaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

We had an old time crystal hunter rejoin our crystal club. He brought in a number of well formed and terminated schorl crystals. They ranged from pencil to thumbsize in thickness and a couple crystals exceeded 3 inches. Well, we got excited about that and so he helped lead a field trip to the site. When we got to the spot near Badger Mtn, he said he hadn't been there since the early 70s and had dug out most of the schorl. Oops, would have been nice to know this ahead of time. Anyway, we gave it a shot. Soon we found garnets. The garnets were fairly small and not gemmy, they were surrounded by mica and resided in the host quartzy pegmatite. Perhaps the garnets are almandine garnets Fe₃Al₂(SiO₄)_3, the color was brownish. I will have to look into that more. Upon careful inspection of the garnets, I noticed that there were small schorl crystals intermixed with the garnets (see picture below). Our leader mentioned that the best schorl could be found in quartz chunks. Evidently when these quartz chunks are put in a freezer the schorl will sometimes pop out. Schorl must contract more than quartz. Our leader said that schorl could also be found within feldspar, but is nearly impossible to extract without breaking the crystals. Seems to me a few pieces of nice tourmaline sticking out of the host rock is just as appealing as single tourmalines frozen out of the quartz... and so the hunt was on. My nephew Andrew won the prize and found a perfectly terminated pencil thick 2 inch long tourmaline (float). I found garnets and tourmaline shards. Perhaps tourmaline does not get along well with my crack hammer (kidding). My rockhounding friend Bob, found a broken but well terminated tourmaline. While the trip was not well attended everyone went away with something collectible. I think some more prospecting in the area might turn up a better spot that has not already been prospected quite so much. Until then its back to Lake George for smoky quartz and amazonite!

Looking for float or debris late in the day... somewhat relaxing pose

Andy and I watching my nephew pull out tourmaline pieces

Fragmented tourmaline resting over garnet on matrix

Dime-size garnet

One of Bob's tourmaline finds

Crystals in Miarolitic Cavities of Lake George Pegmatites

My rock hounding friend and I have returned to Lake George in search of crystals. We've had a slow start to the 2013 season because of the cold and snow we've had this spring. So far we haven't had much success, but perseverance and observation are key to finding the miarolitic cavities that contain the much sought after crystals. The miarolitic cavities or vugs is where the heated mineral enriched liquid cavities within the Lake George pegmatites produce crystals. As the pegmatites and cavities cooled over 1 billion years ago the crystals formed in the solidifying pockets. As the pockets contiued to cool they crack and end the crystal forming process. Due to weathering and other erosion processes many of these now collapsed crystal pockets are near the earth's surface and ready for harvesting. The difficulty in finding the collapsed pockets stems from hundreds of people digging through the pegmatites and finding the easy to get crystals. Sometimes a portion of the pegmatite is exposed to the surface and creates "float" crystals. The crystals are called float because they are on the surface and detached from their source. Inexperienced rock hounds often pick up these float crystals or keys to the location of the crystal pocket without realizing they've not only missed the mother lode, but also erased evidence for others to find the crystal pocket. One prospector at Lake George uses track hoes to dig down over 20 feet into the earth's crust to discover and follow pegmatites opening up crystal vugs. So far this year I have found 4 collapsed vugs with crystals, all within 1-3 feet of the surface. Unfortunately the pockets were small and many of the crystals were either broken or had quartz overgrowth. The breakage can be a result of either the original pocket rupturing under pressure during crystal formation, or the grinding of crystals against each other over millions of years of frost thaw cycles and other erosion processes. I believe the overgrowth of quartz over the smoky crystals is a result of a later infusion of quartz into the vug. This quartz covers the smoky crystals to varying degrees and if not gemmy, hoods the smoky crystals making them somewhat unsightly and not very desirable.  If the hooding quartz is smoky or clear, the crystals are more desirable and are described as phantom smoky crystals as the original smoky is visible through the later quartz hooding. These hooded crystals are highly prized.

This smoky cluster has a lot of overgrowth and is rather unsightly. Too bad the bluish fluorite (lower left) was not larger

A nicer crystal grouping found on Monday... no quartz overgrowth (crystals 1.5-2 inches)

Vug Clay at Lake George

Another day rockhounding at Lake George and another pocket of crystals. This is one of the first times I've run into blackish purple greasy clay in a crystal pocket.  Most often the clay is either reddish (iron-stained) or yellow. I've also run into grayish material. The particular pocket I was in this day had blackish purple clay and the crystals were not very collectible due to breakage and additional quartz overgrowth. I like clear quartz over smokys which gives the illusion of phantoms or ghost smoky crystals, but not the granular/rough opaque quartz overgrowth on smokys. We sometimes say the smokys are hooded when this happens. I got into a discussion with my digging buddy Bob regarding colors of clay and if that has any correlation to the quality of crystals found in the clay.  We both have had very good luck with red clay and poor luck (crystal quality) with blackish purple clay. I'm afraid our sample size is not sufficient to make any conclusions. Anecdotally crystals found in the yellowish clay are harder to clean and the smokys don't seem to have the same lustrous exterior as those found in the red clay.  This got me to thinking is the clay in the pocket from the surrounding material or is the clay a result of the soup left in the miarolitic pocket after crystal formation. Since every pocket I've ever found has been broken imploded/exploded I'm guessing it's a mixture of leftover vug material and surrounding decayed/weathered pegmatite.  I decided to do a search on the internet and not only was there a discussion about clays in miarolitic cavities but it concentrated on the Pikes Peak Batholith see Mineralogy and Provenance of clays in Miarolitic Cavities of the Pikes Peak Batholith, Colorado. by Kile.  While this article was a little above my head scientifically speaking, it seems part of my hypothesis is correct, that the clay is from both the leftover vug material and surrounding weathered pegmatite. The article mentioned the clay varieties smectite, Illite and kaolinite being predominant in the vugs (never knew there was so much to know about clay). The author also mentioned infusion of material from hydrothermal processes after the pockets form. I think some of the fluorites are formed that way. My bigger question was unanswered, does the color of the clay in a pocket have any correlation to the quality of the crystals therein. Does the color of the clay indicate a higher concentration of elements inhibiting crystal formation or luster? Enough investigation for one day. Here are some pictures of the latest dig....

Checking out the latest crystals

A pretty gemmy crystal



Darker area is pocket with broken quartz crystals

Restaking a claim & late snow at Lake George

A friend of ours has a few claims north of Lake George and he has been sick for awhile. He asked us if we would be willing to restake his claim this year(what are friends for?). Well this turned out to be more work than we thought. Thank god for GPS. We found the first claim marker quite easily, but converting between coordinate systems and searching for vandalized posts was not what we expected. We got two claims restaked, but the weather set us back so that we will have to try again next week. We set out to restake the second set of claims only to be turned back by the weather. We thought there would be snow on the claim but didn't realize the depth and extent of the last snowstorm up in the mountains. Often a snowstorm will hit the front range mountains of Colorado and leave interior mountain areas like Lake George high and dry. Not so with the latest storm as we found out. Our trip was not totally wasted. We determined a field trip near Wilkerson Pass (9500ft) should be cancelled due to snow and instead of restaking claims we rockhounded on a sunny unclaimed area near Lake George (elev 8200ft). Elevation makes quite a difference with spring storms. I even managed to find a pocket of smoky crystals. By midafternoon over half the snow was melted and this helped me find a pocket. The pocket was small and the crystals were beaten up for the most part. Still it was my first find of the year.

Doing the forest service work, this tree has been across the rd for 6+ months!

Marker was thrown by someone into this brush pile. Supporting rock caron was about 50ft away down the hill

Pretty small crystal cache from pocket discovery, couple good ones I think

Still snow at Wilkerson Pass. Temperature was 23F on west side of pass near Hartsel. Time to go back to Lake George where the sun is shining and find those crystals depicted above!