stonedape
starting to spend too much on rocks
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Post by stonedape on Aug 10, 2016 12:54:11 GMT -5
I think this is Hematite but since I do not know I figure I would ask.
Its magnetic. Feels heavy and has a metallic middle
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Deleted
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Post by Deleted on Aug 10, 2016 13:02:03 GMT -5
Hematite isnt magnetic.
Magnetite is, but that doesnt look like any magnetite that I have seen.
Both are quite soft and easily scratched with a steel knife blade.
Can you do a specific gravity?
Is the last pic a cut area?
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stonedape
starting to spend too much on rocks
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Post by stonedape on Aug 10, 2016 13:16:48 GMT -5
Hematite isnt magnetic. Magnetite is, but that doesnt look like any magnetite that I have seen. Both are quite soft and easily scratched with a steel knife blade. Can you do a specific gravity? Is the last pic a cut area?
Yes...I was trying to figure it out and I ground off a little point on the end of it. (the lines im pretty sure are from the grinding wheel I used) I think I can do a specific gravity test. I haven't done one but I have read on how to do them and I have a scale.
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Deleted
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Post by Deleted on Aug 10, 2016 13:18:46 GMT -5
Looks like you certainly have a magnetic metal there. The color of the corrosion indicates iron. Now, about that specific gravity? Failing that, polish that window, then etch in iron chloride solution to look for the triangular crystals diagnostic of iron meteorites... vegasjames
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stonedape
starting to spend too much on rocks
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Post by stonedape on Aug 10, 2016 13:38:16 GMT -5
Looks like you certainly have a magnetic metal there. The color of the corrosion indicates iron. Now, about that specific gravity? Failing that, polish that window, then etch in iron chloride solution to look for the triangular crystals diagnostic of iron meteorites... vegasjames2.85 SG
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Deleted
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Post by Deleted on Aug 10, 2016 13:41:24 GMT -5
Looks like you certainly have a magnetic metal there. The color of the corrosion indicates iron. Now, about that specific gravity? Failing that, polish that window, then etch in iron chloride solution to look for the triangular crystals diagnostic of iron meteorites... vegasjames2.73 SG Any chance of a math error? Even the oxides are way heavier than that.
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stonedape
starting to spend too much on rocks
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Post by stonedape on Aug 10, 2016 13:44:29 GMT -5
I measured the rock at 11.5g
Put a small cup of water on it and zeroed it out. Had rock on a string and lowered it into the cup so it didn't touch the sides or bottom and got 4.0g
11.5÷4.0= 2.875
Is this how you get the specific gravity?
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Deleted
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Post by Deleted on Aug 10, 2016 13:50:20 GMT -5
That would be 2.875 but still...
Hmm....
I have no clue.
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stonedape
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Post by stonedape on Aug 10, 2016 13:52:53 GMT -5
That would be 2.875 but still... Hmm.... I have no clue. Maybe cause it has a thick coat of iron/rust and a relatively smaller metal interior? Not sure but with that specific gravity it is most like not a meteorite from what I have read. Iron meteorites have a SG of 7 or higher.
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Deleted
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Post by Deleted on Aug 10, 2016 13:56:29 GMT -5
You edited same time as my post.
I'm thinking you need to polish that window to see if the material is full of has bubbles.if so,man made.
Magnetite is over 4 I think.
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stonedape
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Post by stonedape on Aug 10, 2016 14:04:16 GMT -5
You edited same time as my post. I'm thinking you need to polish that window to see if the material is full of has bubbles.if so,man made. Magnetite is over 4 I think. I don't have the means to polish it except for my tumbler and that would take a month.
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Deleted
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Post by Deleted on Aug 10, 2016 14:56:38 GMT -5
And it probably wont work.
No lapidary class near you?
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Post by Peruano on Aug 10, 2016 16:14:46 GMT -5
Could it be that the rock is extremely soft, as in a mud or silt stone? I guess the streak is red/brown. I'm guessing a sedimentary rock with zero value in lapidary.
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Deleted
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Post by Deleted on Aug 10, 2016 16:28:26 GMT -5
Could it be that the rock is extremely soft, as in a mud or silt stone? I guess the streak is red/brown. I'm guessing a sedimentary rock with zero value in lapidary. Notice the metallic interior on the windows end? I have to agree that the SG points to somthing not so sexy...
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stonedape
starting to spend too much on rocks
Member since July 2016
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Post by stonedape on Aug 10, 2016 17:03:05 GMT -5
And it probably wont work. No lapidary class near you? I am uncertain. We do have a big university here so maybe I'll ask someone there.
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Post by vegasjames on Aug 10, 2016 17:56:53 GMT -5
Not a meteorite. The surface it too rough to be an iron meteorite. Rough surfaces get ablated off coming through the atmosphere, unless the meteorite breaks up low forming shrapnel. But this is not shrapnel.
Normally I wold say do a streak test on some porcelain. Hematite leaves a red streak and magnetite leaves a grayish streak. Iron meteorites do not leave a streak.
The low SG though leads me to believe that it is probably some form of slag.
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gemfeller
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Post by gemfeller on Aug 10, 2016 18:41:34 GMT -5
Looks to me like it's a badly rusted chunk of scrap iron. You say it's "heavy" to heft so your S.G. reading must be wrong. Bear in mind that a combination of iron oxide and metal won't give an accurate S.G. for either one. Even considering that I think your method of testing S.G. may be in question. To illustrate the principle, this is a miniature scale I use for testing S.G. of small faceted stones when traveling . First the item is weighed directly on the scale pan and the weight noted. In the case of this scale I add a platform above the pan with the wire suspension device resting on the pan but not touching the platform. The small pan is placed on the suspension device and is lowered (with specimen) carefully into the container that's filled with water. All bubbles must be gently shaken free or the result will be wrong. With small specimens I take 3 readings and average them.
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stonedape
starting to spend too much on rocks
Member since July 2016
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Post by stonedape on Aug 11, 2016 10:27:28 GMT -5
Not a meteorite. The surface it too rough to be an iron meteorite. Rough surfaces get ablated off coming through the atmosphere, unless the meteorite breaks up low forming shrapnel. But this is not shrapnel. Normally I wold say do a streak test on some porcelain. Hematite leaves a red streak and magnetite leaves a grayish streak. Iron meteorites do not leave a streak. The low SG though leads me to believe that it is probably some form of slag.
I think the possibility of my specimin being a meteorite is low. However the chance is not 0%. There have been meteorites found with a low SG but they are rare. Also (from what I have read) iron meteorites that have been on the ground a long time will "rust" so to say. My rock looks very similar (to me) to the meteorite pictured in this link below. I realize I am a amateur which is why I am here asking. Thanks for replies.
meteorites.fieldmuseum.org/node/18
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stonedape
starting to spend too much on rocks
Member since July 2016
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Post by stonedape on Aug 11, 2016 10:32:28 GMT -5
Looks to me like it's a badly rusted chunk of scrap iron. You say it's "heavy" to heft so your S.G. reading must be wrong. Bear in mind that a combination of iron oxide and metal won't give an accurate S.G. for either one. Even considering that I think your method of testing S.G. may be in question. To illustrate the principle, this is a miniature scale I use for testing S.G. of small faceted stones when traveling . First the item is weighed directly on the scale pan and the weight noted. In the case of this scale I add a platform above the pan with the wire suspension device resting on the pan but not touching the platform. The small pan is placed on the suspension device and is lowered (with specimen) carefully into the container that's filled with water. All bubbles must be gently shaken free or the result will be wrong. With small specimens I take 3 readings and average them.
I think it has a pretty wide crust on it. The outer crust isn't flaky at all as a old piece of iron would be so I really do not think it is scrap iron.
The SG could be off because of the thickness of the crust. Also I am almost certain my SG reading is correct. I went through the procedures and instructions again and got the same result. Would Hematite have a solid metal interior?
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gemfeller
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Post by gemfeller on Aug 11, 2016 11:25:04 GMT -5
First, your S.G. number is in the range of Abalone shell. I can't think of any magnetic metal with such low density. Magnetic metals are iron (7-7.9), nickel (8.9) and cobalt (8.9).
Second, you can't get an accurate S.G. by checking 2 materials of different densities i.e., the oxide crust and the metallic interior. At best you'll get an average of the 2.
I have no idea what your specimen is. Take it to a specialist as previously suggested.
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