Rockin the Rockies

Rockin the Rockies
Rock Hounding

Monday, August 11, 2014

Ferruginous Quartz & Float Crystals at Lake George

My rockhounding partner and I decided to try a different area of Lake George, one we hadn't prospected much for a couple of years. The rains have been rather heavy lately so we thought we might have some luck finding crystals that Mother Nature had unearthed. One of the best ways to find crystal pockets is to prospect for quartz. Smoky quartz with faces is most desireable, but grey quartz with a face or two is worth following up as well. Amazonite is sometimes found with white quartz, so white quartz can be an indicator and should be carefully examined when field collecting as well. On this trip we planned to do considerable prospecting and thought our chances good for finding crystals due to the last few months of water erosion. Heavy rain can expose new pegmaites or loosen surface crystals and make them more visible. Surface crystals are called float. Float crystals originate in a pocket and are weathered out of the crystal pocket usually transported downhill from their source. When I find good float (quartz with faces) I generally poke around a little bit and try to figure where the quartz came from by tracing the float quartz uphill. Quite often I'm led to an old dig, but occasionally I make a new discovery. Today while prospecting I found some fairly nice float and followed it uphill. The float quartz looked very promising, so good that I found a few collectible float crystals.
Float double terminated with cathedraling scepter
 When following float you generally only have to dig a few inches down. Hopefully the float will become more concentrated and deeper as you dig along and lead to a crystal pocket. As I scanned for float I noted a small depression in the ground above me. I thought if it was a dig, it was very old... After digging and finding several float crystals I hit aluminum foil. At this point I was pretty sure the depression was an old dig and I was just rummaging through some missed float crystals from a previous prospector's crystal pocket. As an aside, pack out what you bring into the forest. I continued digging (less carefully) and arrived at some broken pegmatite around the now obvious old dig. Not an entire waste of the morning as I did find some collectible float crystals. I decided it was time to resume prospecting and continued my search. Meanwhile I got an excited call on our two-way radios from my digging partner. He had found some white quartz and digging down led him to some ferruginous quartz crystals. I had just settled down doing some digging of my own after following quartz, but the quartz I was finding was hooded with white quartz over grey on the crystals. Bob sounded excited about his find and a rumble of thunder overhead persuaded me to search him out on the way back to the truck. We know the area quite well, so when Bob gives directions he is usually pretty easy to find. A few pick axe knocks on surrounding rocks also helps locate his site. Bob was down nearly 4 feet and pulling out interesting plates of red coated quartz crystals. The red coating appears to be a thin layer of iron rich quartz covering white crystals.
Cathedraling plate of ferruginous crystals

Fist size clusters of ferruginous quartz clusters
I have only run into this once before and never in such large quantities as what Bob was finding. So Bob provided the entertainment this afternoon. We got a little wet, but there is still a pocket of crystals waiting for me on the other side of the hill.

1 comment:

  1. Waw, you had some quality time in the hills this summer, for sure... I was hoping to get some quality time to prospect several pegmatites I have located months ago on the geological map of my place (Southern France) but couldn't, mostly because of workings at the parents' home. Oh, well, next time. I'm glad you provided the eye candy once again, so I had my crystal fix :)

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