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Author Topic: What is this object that was retrieved from a lake?  (Read 5341 times)

Offline TashaFaith

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My co-worker found this rock in Greers Ferry Lake.
« Last Edit: 29/03/2012 19:10:49 by chris »


 

Offline CliffordK

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Re: LOOKING TO IDENTIFY
« Reply #1 on: 28/03/2012 22:11:08 »
What happens when you stick a magnet to the object?
 

Offline Ophiolite

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Re: LOOKING TO IDENTIFY
« Reply #2 on: 28/03/2012 22:17:05 »
One thing is for sure is that it is not a rock. It is a rusted fragment of a metal pole or beam, probably support structure for a jetty.
 

Offline TashaFaith

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Re: What is this object that was retrieved from a lake?
« Reply #3 on: 30/03/2012 15:26:32 »
A magnet will not stick to it
 

Offline RD

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Re: What is this object that was retrieved from a lake?
« Reply #4 on: 30/03/2012 16:13:37 »
A magnet will not stick to it

possibly cement which has taken on the shape (and rust) of a rectangular iron girder, i.e. a cement cast.
« Last Edit: 30/03/2012 17:14:49 by RD »
 

Offline Ophiolite

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Re: What is this object that was retrieved from a lake?
« Reply #5 on: 30/03/2012 17:18:18 »
A magnet will not stick to it
That is surprising. I've assumed a scale, imagining the top view being about 1" to 1 1/2" broad. Is that accurate?
 

Offline TashaFaith

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Re: What is this object that was retrieved from a lake?
« Reply #6 on: 30/03/2012 20:19:51 »
Yes that's an accurate estimated measurement
 

Offline TashaFaith

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Re: What is this object that was retrieved from a lake?
« Reply #7 on: 30/03/2012 20:22:51 »
Any ideas on how to find out what exactly it is? He really wants to know and i agreed to help
 

Offline CliffordK

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Re: What is this object that was retrieved from a lake?
« Reply #8 on: 30/03/2012 23:39:29 »
Ok, I struck out with the magnet    :(

What about conductivity?  Do you have a multimeter that you can set on ohms, and check for conductivity?  I like to try to get a little bit of bite into the material with the leads...  if you don't mind, perhaps you could scratch it slightly in an inconspicuous area.

You probably don't want to break it, but does it have any flex?

Can you shine any light through it in a dark room?
 

Offline RD

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Re: What is this object that was retrieved from a lake?
« Reply #9 on: 31/03/2012 09:19:53 »
I'm sticking with my accidental concrete cast made with rusty mold hypothesis.
Here is a deliberate concrete cast  ...


http://www.dimensionsguide.com/dimensions-of-a-hollow-block/
« Last Edit: 31/03/2012 09:24:32 by RD »
 

Offline Ophiolite

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Re: What is this object that was retrieved from a lake?
« Reply #10 on: 02/04/2012 08:15:39 »
Yes that's an accurate estimated measurement
Tasha, I'm absolutely stumped. Are you quite certain it is not magnetic? The magnet you checked with was a strong one and you tested it on something to assure yourself it was indeed a magnet? Excuse me asking these questions, it's just that I can't see a viable explanation for what it is other than my original thought. I'm afraid RD's cast explanation does not explain the deformed character of the piece which bears all the appearance of being metallic.
 

Offline TashaFaith

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Re: What is this object that was retrieved from a lake?
« Reply #11 on: 02/04/2012 14:44:17 »
I'm positive it was a strong enough magnet and indeed was a magnet  :P lol. no need to be sorry.
 

Offline TashaFaith

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Re: What is this object that was retrieved from a lake?
« Reply #12 on: 02/04/2012 14:48:08 »
It does not have any flex nor does light shine through it. He doesn't have a multimeter but he said his nephew does. Will see if we can't test it asap. Any other ideas or suggestions on where i can find out?
 

Offline CliffordK

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Re: What is this object that was retrieved from a lake?
« Reply #13 on: 03/04/2012 05:36:09 »
I think the problem that many of us are having is that it looks man-made. 
Cube/Trapezoid shaped.
Hollow, with a bottom.
more or less uniform sides.
Appears to be rust colored, but there are  many brown things in the world.

So... we have:
  • some kind of malleable cube that has been deformed.
  • some kind of a cast of a square object, with the original square object missing.

So, I would list the materials I could think of as:
  • Steel/Iron.  Apparently it isn't magnetic.
  • Some other metal.  Bronze?
  • Plastic
  • Rubber
  • Ceramic or concrete
  • Perhaps a natural concretion?

Density might give some kind of an indication.  A rubber or plastic might be a little lighter than metals.  Ceramics might be more intermediary.

Perhaps digging into it to figure out what the surface is like, and what is sub-surface.
Better dimensions?  Height, width, thickness of wall. 

More information about where it was found.  How big of a lake?  Boats?  Docks?  Houses? etc.
 

Offline damocles

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Re: What is this object that was retrieved from a lake?
« Reply #14 on: 03/04/2012 11:52:33 »
I would not rule out steel on the basis of a failure to detect ferromagnetism; many special purpose steels have low magnetic permeability, even approaching 1 (non-magnetic; iron is a few tens of thousands). This applies particularly to stainless steel:
http://www.bssa.org.uk/faq.php?id=24

The article is probably some part of the fit-out of a yacht or small launch, made of stainless to minimize rusting.

(later addition:)

From CliffordK
Quote
More information about where it was found.  How big of a lake?  Boats?  Docks?  Houses? etc.

I also think that providing this sort of information is important. I had been assuming from the name 'Greers Ferry Lake' that it had had at least one boat on it!
« Last Edit: 05/04/2012 01:17:55 by damocles »
 

Offline OokieWonderslug

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Re: What is this object that was retrieved from a lake?
« Reply #15 on: 07/04/2012 01:41:20 »
I have seen this before and know what it is. It is the weathered joint of a rock. There was some soft rock. The rock fractured into a block. Water laden with either limestone or iron flowed through the joint and cemented particles together until the joints became filled. Erosion stepped in and eroded the mother rock away. But since the joint was made of harder stuff it remains. Sorta kind like a cast, but not really.

Thy are fairly common in West Virginia.
 

Offline Airthumbs

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Re: What is this object that was retrieved from a lake?
« Reply #16 on: 08/04/2012 18:47:19 »
It looks to me like someone has poured a cement like mixture into a plastic bag and then inserted a wooden pole into it!  Why someone would do that at the edge of a lake is beyond my quay skills :)

Looks like Ookie has cracked it!
« Last Edit: 08/04/2012 18:50:19 by Airthumbs »
 

Offline JimBob

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Re: What is this object that was retrieved from a lake?
« Reply #17 on: 23/04/2012 02:16:48 »
It looks to me to be a very old blacksmith's crucible for melting small amounts of metal or metal ore for assay or fine silver-gold work.
 

Offline njrich

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Re: What is this object that was retrieved from a lake?
« Reply #18 on: 13/05/2012 12:44:47 »
I do a lot of metal detecting at the beach and find all sorts of oddities and when I can't tell what I've got I go to the treasurenet forum.  These folks have seen it all.  Give it a shot.  forum.treasurenet.com/
 

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Re: What is this object that was retrieved from a lake?
« Reply #18 on: 13/05/2012 12:44:47 »

 

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