Can anyone confirm if this is Basalt?

Steve in PA

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Jul 5, 2010
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I found this yesterday in a plowed field in SW Pennsylvania. I was on my way to check out a section of the field when I got a signal on my metal detector and realized the signal was from this rock. When I picked it up, it was unusually heavy so I figured I better take it home and check it out. I thought it might be a Meteorite, but the thing that concerns me is there are a few voids on the surface indicative a slag, but this doesn't look like any slag I've ever seen and I don't know what it would be doing in rural farmland. It is magnetic. I was told on the Meteorite forum that it could be Basalt. This field also has petrified wood scattered throughout.

Here are pictures from all angles.

With tape measure and magnet.
Top with Magnet.jpg

Two of the four sides:
Meteorite  - 1.jpg Meteorite - 2.jpg

The other two sides:
Meteorite - 3.jpgMeteorite - 4.jpg

Both ends:
Meteorite End - 1.jpg Meteorite End - 2.jpg

Finally I'll throw in some petrified wood photos from the same field
Pet Wood - all.jpg Four Pieces - 1.jpg
Big Piece.jpgFour Pieces - 2.jpg
 

Looks too coarse grained to be a basalt. I don’t think basalt would attract a magnet like that.
Looking up Basalt on the Net, I came across this:
Accessory minerals present in relatively minor amounts include iron oxides and iron-titanium oxides, such as magnetite, ulvospinel, and ilmenite. Because of the presence of such oxide minerals, basalt can acquire strong magnetic signatures as it cools
 

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That piece looks like basalt to me. Most of the basalt on southern Idaho's desert is magnetic to one degree or another. If you run a magnet over an anthill out there, you'll have a big glob of 1/8" particles stuck to it. But the amount of iron will vary widely.
Jim
 

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It looks a bit more like a sedimentary rock to me from the photos, but it is really tough to say from these images alone. Maybe break off a pieces and photograph a fresh surface? Nice pet wood finds!
 

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It appears to contain mica. If so that leaves Basalt out but Andesite commonly contains mica.

It does appear to have a volcanic origin. The rocks are so old where you found this it's entirely possible it's a metavolcanic rock, or as suggested by fuss metasedimentary rock.
 

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That piece looks like basalt to me. Most of the basalt on southern Idaho's desert is magnetic to one degree or another. If you run a magnet over an anthill out there, you'll have a big glob of 1/8" particles stuck to it. But the amount of iron will vary widely.
Jim

Look up andesite. It's midway between rhyolite and basalt and contains ferro magnesium so might trip a detector. Gary

It looks a bit more like a sedimentary rock to me from the photos, but it is really tough to say from these images alone. Maybe break off a pieces and photograph a fresh surface? Nice pet wood finds!

It appears to contain mica. If so that leaves Basalt out but Andesite commonly contains mica.

It does appear to have a volcanic origin. The rocks are so old where you found this it's entirely possible it's a metavolcanic rock, or as suggested by fuss metasedimentary rock.
Thanks for the replies. Now I'm leaning toward high grade Iron Ore?
Elemental Analysis of my mystery rock (treasurenet.com)
 

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