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Author Topic: What is this rock and why is it so light for its size?  (Read 3581 times)

Offline Dustinbad23

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Hello, i was wandering if anyone could tell me what kind of rock this is. My dad found it in East Tennessee a few years ago. It is covered in holes on its topside, and its weight is very light for a rock of this size. Thank you
« Last Edit: 06/12/2013 17:58:47 by chris »


 

Offline cheryl j

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Re: unknown rock
« Reply #1 on: 05/12/2013 22:03:24 »
It looks a little like  pumice stone. I don't think there are volcanoes in Tennessee, though. Perhaps someone was sanding their toes and it fell out of their pedicure kit.
« Last Edit: 05/12/2013 22:06:29 by cheryl j »
 

Offline Dustinbad23

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Re: unknown rock
« Reply #2 on: 05/12/2013 23:48:35 »
It was found in a small river bed, and the river is formed by many small creeks that all dead end in the mountains where we live. I checked and there is no known volcanoes around here, though i didnt think there was. So if it is pumice, any ideals as to how it got here?
 

Offline RD

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Re: unknown rock
« Reply #3 on: 06/12/2013 00:00:14 »
Unusually for rock , some pumice can float ... http://en.wikipedia.org/wiki/Pumice_raft
so can be transported across oceans.
« Last Edit: 06/12/2013 00:02:10 by RD »
 

Offline Dustinbad23

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Re: unknown rock
« Reply #4 on: 06/12/2013 00:27:27 »
I dont know alot about science or geology but after looking at other pumice rocks online i dont think this is pumice. But like i said i am no expert at all. I will attach a picture to show what the bottom looks like as it looks alot different that the top. The bottom has a few holes but they are all very tiny
 

Offline RD

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Re: unknown rock
« Reply #5 on: 06/12/2013 02:45:20 »
 

Offline Dustinbad23

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Re: unknown rock
« Reply #6 on: 06/12/2013 03:05:13 »
I already tried to put it in my sink full of water & it stayed on the bottom. After removal from the water it now smells funny, i cant describe the smell. And it now has more orange on one side after being in the water. I dont know if any of that info will help or not. Oh and thank you all for the responses.
 

Offline Bass

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Re: unknown rock
« Reply #7 on: 06/12/2013 05:13:29 »
I suspect that is weathered limestone, especially if it weathers an orange color (go Vols- though actually I'm a Commodore).  All it would take is a bit of silica to form the framework, which is not uncommon in limestones in Tennessee.
 

Offline RD

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Re: unknown rock
« Reply #8 on: 06/12/2013 06:09:16 »
« Last Edit: 06/12/2013 06:15:30 by RD »
 

Offline chiralSPO

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Re: What is this rock and why is it so light for its size?
« Reply #9 on: 13/12/2013 03:37:42 »
If it's limestone a drop of vinegar on it will fizz. (This will corrode the rock a little, but it looks pretty weathered already...) Of course, fizzing doesn't prove it's limestone, but it would narrow the choices a lot.
 

Offline OokieWonderslug

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Re: What is this rock and why is it so light for its size?
« Reply #10 on: 13/12/2013 16:18:45 »
That is probably slag from a coal fired furnace of some sort. I have seen coal residue that looks like that. The clinkers are light and filled with vesicles where the coal was once embedded. It probably washed down the river from somewhere else.
 

Offline Joceeghost

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Re: What is this rock and why is it so light for its size?
« Reply #11 on: 10/02/2014 07:01:36 »
It looks like porous limestone. We use to find in northeast Alabama when i was a kid.
 

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Re: What is this rock and why is it so light for its size?
« Reply #11 on: 10/02/2014 07:01:36 »

 

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