[meteorite-list] question on performing a nickel test

[Michael Murray]

Hi List,

If someone has experience with the Allerderm Nickel test and wouldn't  
mind sharing their knowledge of how to do it...

I am attempting to do a nickel test at home here and I ran into a bit  
of a snag.  I have a piece of iron that most likely is not a piece of  
meteoritic iron that I was using as a test piece.  I sanded a surface  
on it, cleaned it with alcohol several times, got out the trusty  
Allertest NI test kit from Allerderm, placed a drop each of the  
little bottles onto a cotton swab, and placed that on the cleaned  
surface of the metal.  Using this piece of iron as a control piece, I  
wanted to be sure I wasn't doing something in the steps I was using  
that would cause me to get a false positive.  On this test - test,  
the swab turned pink quickly.  If I do the exact steps only add in  
placing a drop of white vinegar on the cleaned surface, wait a couple  
minutes and then apply the nickel test, I get almost a blood red swab  
in just the first second.  The first time I did this test and saw  
this, I thought I had contaminated the surface so I sanded it again  
down to a fresh surface, cleaned it several times again with alcohol  
before attempting the nickel test without vinegar.  Second time, same  
result.  When using a drop of vinegar again, same result - blood red  
quickly.

What am I doing wrong, if anything?  Could I still have contamination  
on the metal that the sanding and cleaning with alcohol is not removing?

Mike in CO