[meteorite-list] EBAY Slag for sale

[Randy Korotev]

At 14:59 05-07-07 Thursday, STARSANDSCOPES at aol.com wrote:
>I don't  know why this slag tests positive for nickel, but it does!


People have been making iron and disposing of the 
waste for several hundred years in this area and 
much of the US.  The most common kinds of local 
meteorwrong I encounter are hematite nodules - 
iron ore - that weather out of the local 
limestone.  This stuff has been used as feed 
stock for mom-and-pop iron smelting operations in 
the Ozarks since the 1800's.  As Tom Phillips 
said, the processes were not as efficient as 
today, so a lot of iron metal was left 
behind.  People have brought us all kinds of 
glassy stuff with metal in it, one of which even had the imprint of a bolt:

http://meteorites.wustl.edu/meteorwrongs/m026.htm


Two months ago a fellow came to my office with 
the ugliest 60-lb chunk of iron I've ever 
seen.  He'd dug it up while "grub hoeing" in 
south St. Louis Co.  There was no smooth surface, 
it was very rusty, and it was full of 
cavities.  It didn't "look like" an iron 
meteorites to me, but I have no experience with 
iron meteorites that have been in the ground for 
100's to 1000's of years, so I really don't know 
what to expect.  In a post 2 months ago, Eric 
Twelker said "Those of us who are lucky enough to 
have hundreds or thousands of meteorites pass 
through our hands possess a store of knowledge 
that has real value to academics that haven¹t had 
this experience."  I agree, and I wish I had that knowledge!

I neglected to get a photo of the thing.  I did a 
quick nickel test, though, with one of those 
nickel allergy test kits and got a positive 
result*.  So, I cut a piece off and analyzed it 
for the Fe, Ni, Co, Au, and Ir.  Strange results:

>Fe   89%
>Ni  600 ppm
>Co   62 ppm
>Ir    1 ppb
>Au   12 ppb

The object cannot be a meteorite because the 
concentrations of Ni and Co are 100x too low for 
metal in any kind of meteorite.  Yet, the 
concentrations of Ni, Co, Ir, and Au are all 
higher that I would expect for iron smelted from 
iron ore.  More weird is that the relative 
concentrations of those elements (ratios) are not 
out of line for an iron meteorite.  It's as 
though the metal is 1% iron meteorite and 99% 
pure iron.  I don't know what this thing is.

Similarly, a fellow from Colorado sent this photo 
and a small sample a couple of years ago:

http://meteorites.wustl.edu/meteorwrongs/m122.htm

It is also a a man-made piece of iron, but one 
with far more Ni and Co than in any iron oxide ore I've ever analyzed.

>Fe   90%
>Ni 2590 ppm
>Co  131 ppm
>Ir  <14 ppb
>Au   85 ppb

I don't get it.

Randy Korotev


* Note that the dimethyl glyoxime [DMG] test for 
Ni is very sensitive.  If it gives a positive 
result for 600 ppm Ni, then it is too sensitive 
to really be of much use in distinguishing 
meteoritic metal from terrestrial metal. A 
negative result should be helpful, however, if the test is done correctly.)