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Is this considered a breccia?


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This is a 45 gram rock I found on a trail the other day. It looks like a breccia of some type. Any ideas guys. Also if you happen to know a good website with good well rounded information about the different types of breccia, this would be helpful as well. I feel like google search is good but kind of aimless.

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No expert, but if it was, I'd say no.

If it was, I suspect it got sucked under the earth in the rock cycle with great heat and pressure and turned metamorphic.

Breccia is a sedimentary rock any rock where fragments are cemented together.  The stuff I would think is breccia does not wear round like your rock, and I think would be much softer.  I think of Breccia as an old piece of broken cement I find lying around. 

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Based on the apparent "flow" lines (lineation) of the biotite, I would go with a Gniess which is a metamorphic type rock.

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Again, still learning, but when I hear Gniess, I think of a taffy looking rock that looks kind of like vanilla pudding and chocolate pudding put in a bowl and stirred once or twice where the lines of chocolate and vanilla are still separated.  There's a type of metamorphic conglomerate that still has the original  rocks clearly visible that I thought this was, which I thought quartzite, but that's not the word for it.

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Conglomerate is made up of more uniform shaped particles and hard packed together.  Brecca's are more non uniform shapes and look to contain more filler (Cementing ) materials. 

Conglomerate is more of a Sedimentary formation situation .   Brecca's were formed via Erosion or grinding of rocks in a Fault type situation...   Fault being a key word when looking for Gold.  

https://www.google.com/search?q=breccia's+stone+photo&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjdlYTR0ObVAhUBV2MKHVx8BU4QsAQIJw&biw=1366&bih=659

Edited by homefire
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On 8/20/2017 at 11:46 AM, chrisski said:

Again, still learning, but when I hear Gniess, I think of a taffy looking rock that looks kind of like vanilla pudding and chocolate pudding put in a bowl and stirred once or twice where the lines of chocolate and vanilla are still separated.  There's a type of metamorphic conglomerate that still has the original  rocks clearly visible that I thought this was, which I thought quartzite, but that's not the word for it.

Chrisski, I think you nailed it. I googled "metamorphic conglomerate" and the first image appears to be most similar to what I have. Though the terminology might not be the correct one, it a great clarification at least. Here is another nice one I found at my brothers the other day. Very nice rock, id love to slice it up at some point.

Thanks everyone and thanks chrisski.

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Edited by Rocky
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So I put the parts together and realized a true breccia's matrix would be rather plain, homogonous, and uncharacterized and not crystallized what so ever as one would find in metamorphic rocks being they where exposed to exteme heat and pressure causing those rocks matrix to change and crystallize. True?? Back to the third grade but I think I get it now!! Thanks guys.

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Both involved Heat and Pressure to be sure .  Just the Origination of the Materials deffer.    Breccia's have not been worn or eroded so much.   Usually only made up of a few types of Material.   Most likely formed in or near the source of Materials at hand.   Conglomerates are just that.  A Conglomeration of Materials  many types most likely from a alluvial flow.  Covered and Cooked with Time and Pressure. 

 

Class Begins .  LOL    After this you will know more then I know about the stuff. 

https://en.wikipedia.org/wiki/Alluvial_fan

https://en.wikipedia.org/wiki/Breccia

https://en.wikipedia.org/wiki/Conglomerate_(geology)

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17 minutes ago, homefire said:

Class Begins .  LOL    After this you will know more then I know about the stuff. 

LOL, exactly what I need. Not gonna lie this reading is probably going to involve the consumption of beer or wine. 

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