Naked Science Forum
Non Life Sciences => Geology, Palaeontology & Archaeology => Topic started by: suzequzi on 12/08/2007 14:50:06
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This rock was found in a field in Southwestern part of Virginia. There are mines in the area (lead maybe). There are marks on the rock that look like drill marks. Any help would be appreciated. [ Invalid Attachment ] [ Invalid Attachment ] [ Invalid Attachment ] [ Invalid Attachment ] [ Invalid Attachment ]
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JimBOB !!..we need JIMBOB !!
WELCOME Suzequzi !
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I just emailed him the link to here...
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I am blushing. I feel needed - gosh !!!!!!!
I have been remiss because I am trying to secure potentially about $500,000,000.00 US (yes, the number of zeros is correct) for myself and the contract negotiations etc., have left my brain the consistency of warm Jello.
NO!!! You can't have any of it. I do not have friends!!!!!!!
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fbestsmileys.com%2Fangry2%2F11.gif&hash=ef77c6e2d50d42acd17192a634104bfe)
The pictures
This was found near a mine. The substance looks amorphous (no crystal structure) and has conchoidal fracturing. This makes it highly likely that it is one of two things - mine slag or chert. There is very little volcanic activity - if any in SW Va. so that obsidian pretty much out. It could be obsidian if it is associated with Native American relics but this is a very slim possibility.
It is most likely glass of some sort. Either from a mine slag heap or a glass factory. It could also be chert since there is a lot of Limestone in SW Va. I favor the chert possibility but I need bigger pictures for me able to tell - possibly.
I must go write another contract (a small one, this time), try to placate a person who has his nose into something he should not even be concerned about and generally do what a manager does.
I'll be back soon, I hope.
JimBob
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Looks like ideal stuff to make a fake batch of these
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Any chance you could tell us how hard the rock is? (can it be scratched by a knife?, penny?, glass?)
Is it transparant? How large is it?
I agree with JB that it appears to be some sort of glass- I don't know of many smelters that produce clear slag.
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Ok, I have tried to scratch this "rock" with a nail, knife, scissors and it doesn't scratch. It does however scratch, glass,and stainless steel. This "rock" looks a bit milky and gets clear. The "rock" looks to have layers. I'll see if i can attach more pictures. [ Invalid Attachment ]
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I took another pic to give you an idea of the size. [ Invalid Attachment ]
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It is a very pretty cool looking blue! Looks crystal like!Almost the texture if that sleek black lava rock..OOOOH I cant recall what they call it... obsedian or something like that.. The texture is close but the color no way.. That is quite pretty!
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yeah conchoidal fracture patterns, no visible crystalline structure does make me think of flint/chert. You do get that in limestones. Looking a high level geological map of the area it seems to be mostly sedimentary rocks (limestone/sandstone) and they do say that there is coal mining in that part of the world. There is no mention of igneous intrustions or volcanic deposits. So that rules out all those weird igneous and metamorphic occurances.
The colour concerns me. I've never seen such a lovely blue in flint.
It could be a lump of glass or perhaps some ceramic used during the mining of coal....
Its so hard to identify from a picture.
pete
inthehills
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the other thing to check is was there any weathering on the surface of the material. Did you find it as it was or did you have to hit something with a hammer?
Was it just lying on the surface or did it come out of a cliff face?
what were the rocks around it like?
was there a lot of this material or was it a one of a kind?
pete
inthehills
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I wish there were a clearer, larger picture to get an idea of its luster. Looks like it could be waxy. If this is true, with a hardness close to that of quartz, conchoidal fracture, and amorphous structure (not to mention the beautiful blue), it seems like it could be some form of chalcedony.
It looks like some kind of cryptocrystalline quartz to me. (identification was never my strongest suit)
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I finally found something that will scratch the surface. An Indian arrowhead. I found some pictures of Obsidian and it looks just like it except for the color. But as far as I know there are no volcanoes in this area. It's still a mystery. Don't know of any glass factories either. Besides, can glass be as hard as this "rock" is.
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Glass is about the middle of the hardness scale, and you need hardened steel to scratch it; a common knife will not do the trick, some files will and a "glass knife" used for cutting panes is made of specially hardened steel. In fact, you do not cut the glass but scratch it and next break it along this scratch.
Your "Indian arrowhead" is probably flint,which is chemically of the same composition as quartz and has the approximately the same hardness.
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I finally found something that will scratch the surface. An Indian arrowhead. I found some pictures of Obsidian and it looks just like it except for the color. But as far as I know there are no volcanoes in this area. It's still a mystery. Don't know of any glass factories either. Besides, can glass be as hard as this "rock" is.
I agree with looking like obsidian except for color.. texture is right as if iy had once flowed..
It is really very beautiful!