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Hay, does anyone know if this is calpopyrite or is it something elses i have found pyrite b4 and it has never looked like this? It came from out of a shale piece from spencer creek near hannable MO.

post-1179-1245202460_thumb.jpg

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it sure looks like calcopyrite to me. i see some rainbow colors at the top of the piece. just to be on the safe side...you better send it to me for further analysis! lol.

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it sure looks like calcopyrite to me. i see some rainbow colors at the top of the piece. just to be on the safe side...you better send it to me for further analysis! lol.

Very good :P

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it is a very heavy specimin might be golena ore?

or andother lead ore

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Hay, does anyone know if this is calpopyrite or is it something elses i have found pyrite b4 and it has never looked like this? It came from out of a shale piece from spencer creek near hannable MO.

At first glance it looks to be the case, but there are some other minerals that can look like that. Can you show us the cross-sections?

Be true to the reality you create.

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At first glance it looks to be the case, but there are some other minerals that can look like that. Can you show us the cross-sections?

post-1179-1245207408_thumb.jpg

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Both pyrite and chalcopyrite have a dark green to greenish-black streak. Crush a small fragment and note the color.

Pyrite is much harder and will scratch a steel knife blade. Chalcopyrite will not.

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I would say it's most likely Pyrite or Marcasite. Generally Chalcopyrite CuFeS2 will form only in the presence of Copper in hydrothermal deposits where it is more likely to be found as a massive specimen than crystallized.

-Dave

__________________________________________________

Geologists on the whole are inconsistent drivers. When a roadcut presents itself, they tend to lurch and weave. To them, the roadcut is a portal, a fragment of a regional story, a proscenium arch that leads their imaginations into the earth and through the surrounding terrain. - John McPhee

If I'm going to drive safely, I can't do geology. - John McPhee

Check out my Blog for more fossils I've found: http://viewsofthemahantango.blogspot.com/

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OK...

I can see there is more of the "rainbow" effect inside, but also that it appears more orange than your usual pyrite. This is a pretty good indicator of copper. I don't know if I would go so far as to call it Calcopyrite, but more likely just a regular Iron pyrite with some copper present.

Be true to the reality you create.

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I would say it's most likely Pyrite or Marcasite. Generally Chalcopyrite CuFeS2 will form only in the presence of Copper in hydrothermal deposits where it is more likely to be found as a massive specimen than crystallized.

There is a lot of marcasite in the Devonian shales around Hannibal. Usually it's in crystalline balls, but I have found some pretty big pieces in the Continental Cement Quarry there.

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There is a lot of marcasite in the Devonian shales around Hannibal. Usually it's in crystalline balls, but I have found some pretty big pieces in the Continental Cement Quarry there.

Color alone rules out Marcasite.

Be true to the reality you create.

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I say it looks like pyrite. Often you cannot tell the type of mineral something is just by looks alone. Color is one way of identifying a mineral, but alone, it can be misleading. Pyrite and chalcopyrite often look similar. This can be confusing to people. I often see pyrite in the shale of that region. And in the easter half of Iowa i have heard of actual pyrite mines (???read about this in an old mineral magazine years ago). To ID it, you would have to do some other tests.

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There used to be a formation with Pyrite "Suns" that grew between the layers of hard black shale in Illinois/Indiana. The pyrite formed microcrystalline flattened round shapes that looked like a sun with rays coming out of the middle. I even heard of a case where a school or church that was built on a foundation of this shale was actually raised up a few inches over time due to the formation of the pyrite. It started to form due to exposure to ground water to the previously sealed rock layers. Pyrite is a very common mineral in sedimentary deposits. In my opinion it's third behind Calcite and Quartz in terms of replacing/preserving fossils.

-Dave

__________________________________________________

Geologists on the whole are inconsistent drivers. When a roadcut presents itself, they tend to lurch and weave. To them, the roadcut is a portal, a fragment of a regional story, a proscenium arch that leads their imaginations into the earth and through the surrounding terrain. - John McPhee

If I'm going to drive safely, I can't do geology. - John McPhee

Check out my Blog for more fossils I've found: http://viewsofthemahantango.blogspot.com/

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Hay, does anyone know if this is calpopyrite or is it something elses i have found pyrite b4 and it has never looked like this? It came from out of a shale piece from spencer creek near hannable MO.

My first impression from this first photograph was that the specimen is a typical big old blob of amorphous chert, or even flint. But, your cross-sectional image a few posts down in this thread reveals little if any obvious conchoidal fracturing so typical of that kind variety of quartz. Still could be chert, or flint (the reddish oxidized surface points to a variety of quartz), yet in cross-section it now looks more like a chunk of dolomite. It's definitely not pyrite (iron sulfide) or even chalcopyrite (copper iron sulfide), for that matter.

http://inyo.110mb.com/dv/alrosetrilobite.htm

A mostly complete trilobite specimen (dang, that one genal spine is not complete--although, perhaps a portion of it is still hidden within the shale) from the Lower Ordovician Al Rose Formation, California.

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I say it looks like pyrite. Often you cannot tell the type of mineral something is just by looks alone. Color is one way of identifying a mineral, but alone, it can be misleading. Pyrite and chalcopyrite often look similar. This can be confusing to people. I often see pyrite in the shale of that region. And in the easter half of Iowa i have heard of actual pyrite mines (???read about this in an old mineral magazine years ago). To ID it, you would have to do some other tests.

Very true. This is because Iron Pyrite is so often enhanced by traces of other metals besides Iron such as Gold and/or copper. Like anything the kettle we call Earth produces there are so many times - the in between.

A simple hardness test can decide the issue. Chalcopyrite has a hardness of 3.5 - 4 on Moh's scale A Knife blade should scratch it easily. Iron Pyrite has a hardnes of 6 - 6.5 so a knife would probably not scratch it, or at least not well.

Be true to the reality you create.

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Ok it isnt magnatic at all even if heated. If you crush or do a streak test it is greyish black. It sraches the steel knife not the other was around. The spacific density is approx 3.8113g/cm^3. Dinasours friend said it was siderite (FeCO3) but it shurr doent look like that but spacific density fits. I am soo confuzzed lol minerals r not my calling can u tell. I have found tones of both types of pyrite and never anyhting like this. I dont think it is a pyrite form?

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Ok it isnt magnatic at all even if heated. If you crush or do a streak test it is greyish black. It sraches the steel knife not the other was around. The spacific density is approx 3.8113g/cm^3. Dinasours friend said it was siderite (FeCO3) but it shurr doent look like that but spacific density fits. I am soo confuzzed lol minerals r not my calling can u tell. I have found tones of both types of pyrite and never anyhting like this. I dont think it is a pyrite form?

Ok...Siderite has a hardness of 3.5 - 4 so if it scratched your knife blade that rules it out as that would usually be around 5.5.

Quartz of any kind is white when you crush it. Chert is a form of quartz.

The streak, the hardness, match Pyrite which has a specific gravity of around 5.0 which is a little heavy but is probably due to the presence of copper (hence the golden color and rainbow).

I still have to go with Pyrite with copper.

Be true to the reality you create.

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Ok...Siderite has a hardness of 3.5 - 4 so if it scratched your knife blade that rules it out as that would usually be around 5.5.

Quartz of any kind is white when you crush it. Chert is a form of quartz.

The streak, the hardness, match Pyrite which has a specific gravity of around 5.0 which is a little heavy but is probably due to the presence of copper (hence the golden color and rainbow).

I still have to go with Pyrite with copper.

I agree.

-Dave

__________________________________________________

Geologists on the whole are inconsistent drivers. When a roadcut presents itself, they tend to lurch and weave. To them, the roadcut is a portal, a fragment of a regional story, a proscenium arch that leads their imaginations into the earth and through the surrounding terrain. - John McPhee

If I'm going to drive safely, I can't do geology. - John McPhee

Check out my Blog for more fossils I've found: http://viewsofthemahantango.blogspot.com/

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