Having Trouble with ID of Rock Specimin. Gold/pyrite/precious metals?

RSMITH

Greenie
Jul 22, 2013
10
16
Denver, Colorado
Primary Interest:
Prospecting
Hello Everyone,

I am new to this website and really excited to be a member. I have recently gotten into precious metal, meteorite, treasure, and fossil prospecting (more so on the precious metals at this point in time). I have read about 10 different books on gold recovery, I have watched 1000 youtube videos, and I also have several years worth of Geology classes from the University of Colorado @ Boulder. My primary major was in Environmental Science but I focused a large majority of my classes in the geology of earth and alien terrestrial environments. This knowledge has really helped me to make more efficient use of my time, however, I realize that I have a long way to go. I have not been finding too many "nuggets," but rather, I have found several rock specimens with wirey metal running through them (some gold, some silver). I was blessed with fantastic vision and I have also ID'd a lot of them under a 40x magnification microscope. So, with all that being said:

I recently found a rock specimen that I am having a difficult time identifying. Utilizing my "somewhat decent" knowledge base, I followed a small drainage basin down to where the ground leveled out and where there were signs of meandering water (now dry). I sought out the lowest depression in the locality and dug down about a foot in the dirt. Before I even started to pan the dirt, I looked down into the hole and saw something glinting in the faint light, 12 inches below the surface.

I pulled the specimen out and immediately thought that I had found a gold nugget, seemingly due to the sheer weight and apparent density of the object. When I washed it off however, I saw that it was a very unique "nugget/rock/specimen/?" The disorienting characteristics are: resembles pyrite in many ways, but much heavier/denser than any pyrite I have felt/seen; The yellow portions are brilliant yellow and do not seem to change under different angles of light; There are also brilliant reds, a little brilliant purple, and glints of silver that are sporadically apparent; *This next characteristic would typically be a nail in the coffin, but keep reading... I also noticed that the specimen had a small portion of beautiful crystal clusters attached to the main nugget/rock. Now, I know that 99 times out of 100, gold will not be affiliated with this type of specimen; Due to the fact that beautiful crystalline structures are generally indicative of a lack of sufficient pressure, mandatory to produce gold veins. However, The colors of this object are unlike any pyrite specimen that I have seen, or have been able to find on the internet. Also, under a microscope of 40x, the crystalline structure of the surface is not structured like a typical pyrite specimen either. Now, there are portions of it that I can tell are pyritic in nature, but a good majority of the surface (at a microscopic level is rounded and has a rather "lumpy" and has precious metal-like appearance. A good portion of the specimen does not change colors to the purples, greens, and browns (as typical pyrite does) when rolled around under a light source, but some parts of it do. And once again, the specimen itself is actually much heavier than any piece of pyrite that I have ever seen. The colors of the surface are also referential to gold and rose gold more so than pyrite. I have included some pictures below and would love some other opinions on this. I also figured out a way to take pictures on my phone through my small microscope (with very steady hands), and I have included those as well. Thank you so much for your time and I look forward to being a member on this website.

*Also, at this point in time, I do not have a sufficient scale in order to calculate the exact density. Before I go to all that trouble, I thought I would put this out to see if any experts can make a visible distinction or hypothesis. IMAG3024-1.jpgIMAG3025-1.jpgIMAG3026-1.jpgIMAG2998-2.jpgIMAG2998-1.jpgIMAG2965-1.jpgIMAG2977-1.jpgIMAG2389-2.jpgIMAG2397-1-1.jpg
 

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Also, I apologize about the darker hue of the 3rd to last picture. There was too much reflection and I had to darken it. I did like the detail in it so I included it.
 

Cool rock what ever it is...
Several ways to go, but it may also be in the Cattierite or Bravoite family.
Just go to Google images and look at them.
Doc
 

The iridescence is typical of a copper sulfide. Perhaps bornite, chalcocite, covellite, digenite, etc...
 

Alright, I found a picture of a chalcopyrite. Although I am still having a trouble making a direct match, I could see this specimen potentially being a variation of a copper pyrite. The biggest factor that is still throwing me off is weight of this object for it's size. It seems far heavier than it should. Are copper pyrites generally heavier due to the copper? Could another mineral be responsible for extra weight? Or would it be the copper?
 

Well, Just guessing if you can eliminate Platinum, Gold, then look at the next heavy's.

Galena
Cassiterite ( Tin )
Tungsten ( Scheelite )

That's where id go next.

johnnysau
 

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